iiinova — where your digital self keeps evolving

Mike Jacobs @mikejacobs.bsky.social · 13h

Start your week with this #yohaku. Fill in cells with 9 different factors of 444 to get totals shown in each row/column. #mathsky #iTeachMath

Use 9 different factors of 444 in a 3 by 3 grid. The numbers in the top row add to 151. The numbers in the middle row add to 80. The numbers in the bottom row add to 19. The numbers in the left column add to 191. The numbers in the middle column add to 42. The numbers in the right column add to 17.

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Mike Jacobs @mikejacobs.bsky.social · 02/10/2026

Here's a #yohaku to take you into the weekend. Fill in cells with 16 different factors of 630 to get totals shown in each row/column AND shaded cells contain prime numbers. #mathsky #iTeachMath

Use 16 different factors of 630 in a 4 by 4 grid. The numbers in the top row add to 101. The numbers in the second row add to 35. The numbers in the third row add to 53. The numbers in the bottom row add to 74. The numbers in the left column add to 30. The numbers in the second column add to 63. The numbers in the third column add to 97. The numbers in the right column add to 73. The central four cells contain prime numbers.

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Mike Jacobs @mikejacobs.bsky.social · 01/10/2026

Try this shady #yohaku. Fill in cells with 9 different integers to get products shown in each row/column AND sum of 4 shaded cells is -3. #mathsky #iTeachMath

Use 9 different integers in a 3 by 3 grid. The numbers in the top row multiply to -78. The numbers in the middle row multiply to 35. The numbers in the bottom row multiply to -330. The numbers in the left column multiply to -20. The numbers in the middle column multiply to -231. The numbers in the right column multiply to 195. The sum of the integers in the 2 by 2 square at the top left of the grid is -3.

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Mike Jacobs @mikejacobs.bsky.social · 30/09/2026

Start your day with this #yohaku. Fill in cells with 9 different factors of 930 to get totals shown in each row/column. #mathsky #iTeachMath

Use 9 different factors of 930 in a 3 by 3 grid. The numbers in the top row add to 36. The numbers in the middle row add to 96. The numbers in the bottom row add to 202. The numbers in the left column add to 98. The numbers in the middle column add to 218. The numbers in the right column add to 18.

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Mike Jacobs @mikejacobs.bsky.social · 29/09/2026

"Start your day with this #yohaku. Fill in cells with 9 different whole numbers to get products shown in each row/column. More free puzzles and books/ebooks for all ages can be found at yohaku.ca

Use 9 different whole numbers in a 3 by 3 grid. The numbers in the top row multiply to 64. The numbers in the middle row multiply to 195. The numbers in the bottom row multiply to 42. The numbers in the left column multiply to 42. The numbers in the middle column multiply to 104. The numbers in the right column multiply to 120.

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Mike Jacobs @mikejacobs.bsky.social · 28/09/2026

Start your week with this #yohaku. Fill in cells with 9 different factors of 580 to get totals shown in each row/column. #mathsky #iTeachMath

Use 9 different factors of 580 in a 3 by 3 grid. The numbers in the top row add to 69. The numbers in the middle row add to 150. The numbers in the bottom row add to 151. The numbers in the left column add to 175. The numbers in the middle column add to 19. The numbers in the right column add to 176.

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Mike Jacobs @mikejacobs.bsky.social · 25/09/2026

Here's a #yohaku to take you into the weekend. Fill in cells with 16 different factors of 660 to get totals shown in each row/column AND shaded cells contain triangle numbers. #mathsky #iTeachMath

Use 16 different factors of 660 in a 4 by 4 grid. The numbers in the top row add to 13. The numbers in the second row add to 160. The numbers in the third row add to 153. The numbers in the bottom row add to 47. The numbers in the left column add to 77. The numbers in the second column add to 28. The numbers in the third column add to 148. The numbers in the right column add to 120. The central four cells contain triangle numbers.

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Mike Jacobs @mikejacobs.bsky.social · 24/09/2026

Try this shady #yohaku. Fill in cells with 9 different integers to get products shown in each row/column AND sum of 4 shaded cells is -8. #mathsky #iTeachMath

Use 9 different integers in a 3 by 3 grid. The numbers in the top row multiply to -125. The numbers in the middle row multiply to -27. The numbers in the bottom row multiply to -112. The numbers in the left column multiply to 90. The numbers in the middle column multiply to 525. The numbers in the right column multiply to -8. The sum of the integers in the 2 by 2 square at the top left of the grid is -8.

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Mike Jacobs @mikejacobs.bsky.social · 23/09/2026

Start your day with this #yohaku. Fill in cells with 9 different factors of 510 to get totals shown in each row/column. #mathsky #iTeachMath

Use 9 different factors of 510 in a 3 by 3 grid. The numbers in the top row add to 120. The numbers in the middle row add to 66. The numbers in the bottom row add to 24. The numbers in the left column add to 46. The numbers in the middle column add to 25. The numbers in the right column add to 139.

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Mike Jacobs @mikejacobs.bsky.social · 22/09/2026

"Start your day with this #yohaku. Fill in cells with 9 different whole numbers to get products shown in each row/column. More free puzzles and books/ebooks for all ages can be found at yohaku.ca

Use 9 different whole numbers in a 3 by 3 grid. The numbers in the top row multiply to 72. The numbers in the middle row multiply to 39. The numbers in the bottom row multiply to 385. The numbers in the left column multiply to 63. The numbers in the middle column multiply to 66. The numbers in the right column multiply to 260.

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Mike Jacobs @mikejacobs.bsky.social · 21/09/2026

Start your week with this #yohaku. Fill in cells with 9 different factors of 460 to get totals shown in each row/column. #mathsky #iTeachMath

Use 9 different factors of 460 in a 3 by 3 grid. The numbers in the top row add to 29. The numbers in the middle row add to 122. The numbers in the bottom row add to 52. The numbers in the left column add to 71. The numbers in the middle column add to 35. The numbers in the right column add to 97.

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Mike Jacobs @mikejacobs.bsky.social · 18/09/2026

Here's a #yohaku to take you into the weekend. Fill in cells with 16 different factors of 960 to get totals shown in each row/column AND shaded cells contain triangle numbers. #mathsky #iTeachMath

Use 16 different factors of 960 in a 4 by 4 grid. The numbers in the top row add to 11. The numbers in the second row add to 60. The numbers in the third row add to 239. The numbers in the bottom row add to 70. The numbers in the left column add to 26. The numbers in the second column add to 155. The numbers in the third column add to 38. The numbers in the right column add to 161. The central four cells contain triangle numbers.

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Mike Jacobs @mikejacobs.bsky.social · 17/09/2026

Try this shady #yohaku. Fill in cells with 9 different integers to get products shown in each row/column AND sum of 4 shaded cells is -2. #mathsky #iTeachMath

Use 9 different integers in a 3 by 3 grid. The numbers in the top row multiply to -102. The numbers in the middle row multiply to -70. The numbers in the bottom row multiply to 143. The numbers in the left column multiply to -273. The numbers in the middle column multiply to 85. The numbers in the right column multiply to -44. The sum of the integers in the 2 by 2 square at the top left of the grid is -2.

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Mike Jacobs @mikejacobs.bsky.social · 16/09/2026

Start your day with this #yohaku. Fill in cells with 9 different factors of 520 to get totals shown in each row/column. #mathsky #iTeachMath

Use 9 different factors of 520 in a 3 by 3 grid. The numbers in the top row add to 79. The numbers in the middle row add to 86. The numbers in the bottom row add to 116. The numbers in the left column add to 182. The numbers in the middle column add to 49. The numbers in the right column add to 50.

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Mike Jacobs @mikejacobs.bsky.social · 15/09/2026

"Start your day with this #yohaku. Fill in cells with 9 different whole numbers to get products shown in each row/column. More free puzzles and books/ebooks for all ages can be found at yohaku.ca

Use 9 different whole numbers in a 3 by 3 grid. The numbers in the top row multiply to 54. The numbers in the middle row multiply to 70. The numbers in the bottom row multiply to 156. The numbers in the left column multiply to 168. The numbers in the middle column multiply to 65. The numbers in the right column multiply to 54.

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Mike Jacobs @mikejacobs.bsky.social · 14/09/2026

Start your week with this #yohaku. Fill in cells with 9 different factors of 240 to get totals shown in each row/column. #mathsky #iTeachMath

Use 9 different factors of 240 in a 3 by 3 grid. The numbers in the top row add to 10. The numbers in the middle row add to 24. The numbers in the bottom row add to 72. The numbers in the left column add to 7. The numbers in the middle column add to 73. The numbers in the right column add to 26.

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Mike Jacobs @mikejacobs.bsky.social · 11/09/2026

Here's a #yohaku to take you into the weekend. Fill in cells with 16 different factors of 840 to get totals shown in each row/column AND shaded cells contain triangle numbers. #mathsky #iTeachMath

Use 16 different factors of 840 in a 4 by 4 grid. The numbers in the top row add to 11. The numbers in the second row add to 360. The numbers in the third row add to 160. The numbers in the bottom row add to 41. The numbers in the left column add to 56. The numbers in the second column add to 166. The numbers in the third column add to 332. The numbers in the right column add to 18. The central four cells contain triangle numbers.

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Mike Jacobs @mikejacobs.bsky.social · 10/09/2026

Try this shady #yohaku. Fill in cells with 9 different integers to get products shown in each row/column AND sum of 4 shaded cells is -3. #mathsky #iTeachMath

Use 9 different integers in a 3 by 3 grid. The numbers in the top row multiply to -78. The numbers in the middle row multiply to -28. The numbers in the bottom row multiply to -220. The numbers in the left column multiply to 154. The numbers in the middle column multiply to -52. The numbers in the right column multiply to 60. The sum of the integers in the 2 by 2 square at the top left of the grid is -3.

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Mike Jacobs @mikejacobs.bsky.social · 09/09/2026

Start your day with this #yohaku. Fill in cells with 9 different factors of 750 to get totals shown in each row/column. #mathsky #iTeachMath

Use 9 different factors of 750 in a 3 by 3 grid. The numbers in the top row add to 82. The numbers in the middle row add to 32. The numbers in the bottom row add to 415. The numbers in the left column add to 386. The numbers in the middle column add to 57. The numbers in the right column add to 86.

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Mike Jacobs @mikejacobs.bsky.social · 09/09/2026

Today saw the start of year 37 for me in teaching!

A n image of a whiteboard in a math classroom saying 'Welcome to MTH1W' and a variety of mathematical objects, graphs and diagrams.

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Mike Jacobs @mikejacobs.bsky.social · 08/09/2026

"Start your day with this #yohaku. Fill in cells with 9 different whole numbers to get products shown in each row/column. More free puzzles and books/ebooks for all ages can be found at yohaku.ca

Use 9 different whole numbers in a 3 by 3 grid. The numbers in the top row multiply to 42. The numbers in the middle row multiply to 105. The numbers in the bottom row multiply to 396. The numbers in the left column multiply to 420. The numbers in the middle column multiply to 154. The numbers in the right column multiply to 27.

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Mike Jacobs @mikejacobs.bsky.social · 07/09/2026

Start your week with this #yohaku. Fill in cells with 9 different factors of 567 to get totals shown in each row/column. #mathsky #iTeachMath

Use 9 different factors of 567 in a 3 by 3 grid. The numbers in the top row add to 51. The numbers in the middle row add to 151. The numbers in the bottom row add to 199. The numbers in the left column add to 199. The numbers in the middle column add to 111. The numbers in the right column add to 91.

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Mike Jacobs @mikejacobs.bsky.social · 04/09/2026

Here's a #yohaku to take you into the weekend. Fill in cells with 16 different factors of 990 to get totals shown in each row/column AND shaded cells contain triangle numbers. #mathsky #iTeachMath

Use 16 different factors of 990 in a 4 by 4 grid. The numbers in the top row add to 25. The numbers in the second row add to 149. The numbers in the third row add to 93. The numbers in the bottom row add to 64. The numbers in the left column add to 12. The numbers in the second column add to 91. The numbers in the third column add to 153. The numbers in the right column add to 75. The central four cells contain triangle numbers.

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Mike Jacobs @mikejacobs.bsky.social · 03/09/2026

Try this shady #yohaku. Fill in cells with 9 different integers to get products shown in each row/column AND sum of 4 shaded cells is -4. #mathsky #iTeachMath

Use 9 different integers in a 3 by 3 grid. The numbers in the top row multiply to 153. The numbers in the middle row multiply to 80. The numbers in the bottom row multiply to -88. The numbers in the left column multiply to 272. The numbers in the middle column multiply to 66. The numbers in the right column multiply to -60. The sum of the integers in the 2 by 2 square at the top left of the grid is -4.

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Mike Jacobs @mikejacobs.bsky.social · 02/09/2026

Start your day with this #yohaku. Fill in cells with 9 different factors of 510 to get totals shown in each row/column. #mathsky #iTeachMath

Use 9 different factors of 510 in a 3 by 3 grid. The numbers in the top row add to 39. The numbers in the middle row add to 22. The numbers in the bottom row add to 205. The numbers in the left column add to 202. The numbers in the middle column add to 45. The numbers in the right column add to 19.

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Mike Jacobs @mikejacobs.bsky.social · 01/09/2026

Start your day with this #yohaku. Fill in cells with 9 different whole numbers to get products shown in each row/column. More free puzzles and books/ebooks for all ages can be found at yohaku.ca

Use 9 different whole numbers in a 3 by 3 grid. The numbers in the top row multiply to 42. The numbers in the middle row multiply to 110. The numbers in the bottom row multiply to 252. The numbers in the left column multiply to 112. The numbers in the middle column multiply to 231. The numbers in the right column multiply to 45.

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Mike Jacobs @mikejacobs.bsky.social · 31/08/2026

Start your week with this #yohaku. Fill in cells with 9 different factors of 570 to get totals shown in each row/column. #mathsky #iTeachMath

Use 9 different factors of 570 in a 3 by 3 grid. The numbers in the top row add to 111. The numbers in the middle row add to 23. The numbers in the bottom row add to 22. The numbers in the left column add to 24. The numbers in the middle column add to 16. The numbers in the right column add to 116.

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Mike Jacobs @mikejacobs.bsky.social · 28/08/2026

Here's a #yohaku to take you into the weekend. Fill in cells with 16 different factors of 624 to get totals shown in each row/column AND shaded cells contain triangle numbers. #mathsky #iTeachMath

Use 16 different factors of 624 in a 4 by 4 grid. The numbers in the top row add to 91. The numbers in the second row add to 211. The numbers in the third row add to 237. The numbers in the bottom row add to 27. The numbers in the left column add to 312. The numbers in the second column add to 112. The numbers in the third column add to 18. The numbers in the right column add to 124. The central four cells contain triangle numbers.

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Mike Jacobs @mikejacobs.bsky.social · 27/08/2026

Try this shady #yohaku. Fill in cells with 9 different integers to get products shown in each row/column AND sum of 4 shaded cells is -5. #mathsky #iTeachMath

Use 9 different integers in a 3 by 3 grid. The numbers in the top row multiply to -66. The numbers in the middle row multiply to -28. The numbers in the bottom row multiply to 130. The numbers in the left column multiply to 60. The numbers in the middle column multiply to 154. The numbers in the right column multiply to 26. The sum of the integers in the 2 by 2 square at the top left of the grid is -5.

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Mike Jacobs @mikejacobs.bsky.social · 26/08/2026

Start your day with this #yohaku. Fill in cells with 9 different factors of 210 to get totals shown in each row/column. #mathsky #iTeachMath

Use 9 different factors of 210 in a 3 by 3 grid. The numbers in the top row add to 14. The numbers in the middle row add to 42. The numbers in the bottom row add to 119. The numbers in the left column add to 115. The numbers in the middle column add to 50. The numbers in the right column add to 10.

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Mike Jacobs @mikejacobs.bsky.social · 25/08/2026

Start your day with this #yohaku. Fill in cells with 9 different whole numbers to get products shown in each row/column. More free puzzles and books/ebooks for all ages can be found at yohaku.ca

Use 9 different whole numbers in a 3 by 3 grid. The numbers in the top row multiply to 102. The numbers in the middle row multiply to 264. The numbers in the bottom row multiply to 65. The numbers in the left column multiply to 510. The numbers in the middle column multiply to 429. The numbers in the right column multiply to 8.

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Mike Jacobs @mikejacobs.bsky.social · 24/08/2026

Nice views of this great blue heron on my run today.

A great blue heron stood in a pond with its long neck stretched out. The heron is framed between two trees.

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Mike Jacobs @mikejacobs.bsky.social · 24/08/2026

Start your week with this #yohaku. Fill in cells with 9 different factors of 315 to get totals shown in each row/column. #mathsky #iTeachMath

Use 9 different factors of 315 in a 3 by 3 grid. The numbers in the top row add to 113. The numbers in the middle row add to 63. The numbers in the bottom row add to 49. The numbers in the left column add to 19. The numbers in the middle column add to 21. The numbers in the right column add to 185.

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Mike Jacobs @mikejacobs.bsky.social · 21/08/2026

Here's a #yohaku to take you into the weekend. Fill in cells with 16 different factors of 432 to get totals shown in each row/column AND shaded cells contain square numbers. #mathsky #iTeachMath

Use 16 different factors of 432 in a 4 by 4 grid. The numbers in the top row add to 14. The numbers in the second row add to 280. The numbers in the third row add to 269. The numbers in the bottom row add to 92. The numbers in the left column add to 23. The numbers in the second column add to 80. The numbers in the third column add to 207. The numbers in the right column add to 345. The central four cells contain square numbers.

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Mike Jacobs @mikejacobs.bsky.social · 20/08/2026

Try this shady #yohaku. Fill in cells with 9 different integers to get products shown in each row/column AND sum of 4 shaded cells is -3. #mathsky #iTeachMath

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Mike Jacobs @mikejacobs.bsky.social · 19/08/2026

Start your day with this #yohaku. Fill in cells with 9 different factors of 144 to get totals shown in each row/column. #mathsky #iTeachMath

Use 9 different factors of 144 in a 3 by 3 grid. The numbers in the top row add to 186. The numbers in the middle row add to 24. The numbers in the bottom row add to 10. The numbers in the left column add to 23. The numbers in the middle column add to 38. The numbers in the right column add to 159.

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Mike Jacobs @mikejacobs.bsky.social · 18/08/2026

Start your day with this #yohaku. Fill in cells with 9 different whole numbers to get products shown in each row/column. More free puzzles and books/ebooks for all ages can be found at yohaku.ca

Use 9 different whole numbers in a 3 by 3 grid. The numbers in the top row multiply to 64. The numbers in the middle row multiply to 91. The numbers in the bottom row multiply to 255. The numbers in the left column multiply to 34. The numbers in the middle column multiply to 168. The numbers in the right column multiply to 260.

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Mike Jacobs @mikejacobs.bsky.social · 17/08/2026

Start your week with this #yohaku. Fill in cells with 9 different factors of 340 to get totals shown in each row/column. #mathsky #iTeachMath

Use 9 different factors of 340 in a 3 by 3 grid. The numbers in the top row add to 58. The numbers in the middle row add to 87. The numbers in the bottom row add to 176. The numbers in the left column add to 23. The numbers in the middle column add to 272. The numbers in the right column add to 26.

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Mike Jacobs @mikejacobs.bsky.social · 15/08/2026

I startled a great blue heron on my run today: there a few more wondrous things than seeing a heron take flight.

A great blue heron taking to flight over a pond fringed with grass and trees.

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Mike Jacobs @mikejacobs.bsky.social · 14/08/2026

Here's a #yohaku to take you into the weekend. Fill in cells with 16 different factors of 576 to get totals shown in each row/column AND shaded cells contain square numbers. #mathsky #iTeachMath

Use 16 different factors of 576 in a 4 by 4 grid. The numbers in the top row add to 12. The numbers in the second row add to 125. The numbers in the third row add to 268. The numbers in the bottom row add to 502. The numbers in the left column add to 25. The numbers in the second column add to 447. The numbers in the third column add to 247. The numbers in the right column add to 188. The central four cells contain square numbers.

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Mike Jacobs @mikejacobs.bsky.social · 13/08/2026

Try this shady #yohaku. Fill in cells with 9 different integers to get products shown in each row/column AND sum of 4 shaded cells is -8. #mathsky #iTeachMath

Use 9 different integers in a 3 by 3 grid. The numbers in the top row multiply to -165. The numbers in the middle row multiply to -91. The numbers in the bottom row multiply to -12. The numbers in the left column multiply to 35. The numbers in the middle column multiply to -78. The numbers in the right column multiply to 66. The sum of the integers in the 2 by 2 square at the top left of the grid is -8.

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Mike Jacobs @mikejacobs.bsky.social · 12/08/2026

Start your day with this #yohaku. Fill in cells with 9 different factors of 330 to get totals shown in each row/column. #mathsky #iTeachMath

Use 9 different factors of 330 in a 3 by 3 grid. The numbers in the top row add to 72. The numbers in the middle row add to 220. The numbers in the bottom row add to 63. The numbers in the left column add to 25. The numbers in the middle column add to 44. The numbers in the right column add to 286.

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Mike Jacobs @mikejacobs.bsky.social · 11/08/2026

Start your day with this #yohaku. Fill in cells with 9 different whole numbers to get products shown in each row/column. More free puzzles and books/ebooks for all ages can be found at yohaku.ca

Use 9 different whole numbers in a 3 by 3 grid. The numbers in the top row multiply to 44. The numbers in the middle row multiply to 130. The numbers in the bottom row multiply to 189. The numbers in the left column multiply to 154. The numbers in the middle column multiply to 117. The numbers in the right column multiply to 60.

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Mike Jacobs @mikejacobs.bsky.social · 10/08/2026

Start your day with this #yohaku. Fill in cells with 9 different factors of 140 to get totals shown in each row/column. #mathsky #iTeachMath

Use 9 different factors of 140 in a 3 by 3 grid. The numbers in the top row add to 41. The numbers in the middle row add to 37. The numbers in the bottom row add to 151. The numbers in the left column add to 152. The numbers in the middle column add to 34. The numbers in the right column add to 43.

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Mike Jacobs @mikejacobs.bsky.social · 09/08/2026

Spotted this beautiful tiger swallowtail today!

A tiger swallowtail butterfly on a peewee hydrangea. The butterfly is yellow with black stripes with some small blue dots near its tail. The hydrangea flowers are small white petals occasionally tinged with pink.

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Mike Jacobs @mikejacobs.bsky.social · 22/07/2026

Spotted this beautiful black swallowtail butterfly on my run today.

A black swallowtail butterfly on some Queen Anne Lace. The butterfly is mainly black with two rows of small yellow dots near the base of its wings. Additionally, between these two rows there are some light blue markings near the centre of the butterfly.

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Mike Jacobs @mikejacobs.bsky.social · 17/07/2026

Spotted this red admiral on the lavender today.

A red admiral butterfly (mainly black with two red diagonal stripes and some white blotches near the wing tips) sat on a patch of lavender.

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Mike Jacobs @mikejacobs.bsky.social · 15/07/2026

Last Thursday, I ran/walked the Edale Skyline in the beautiful Peak District. Today I saw it from above flying back to Canada! The first photo is me on Win Hill. In the second photo this is near the reservoirs near the top right.

A man in white t-shirt and beige shorts by a white trig point on top of a hill looking towards another group of hills on a sunny day.

A group of green and brown hills and some reservoirs seen from a plane flying at 10 000 feet.

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Mike Jacobs @mikejacobs.bsky.social · 07/07/2026

This beautiful marbled white landed on my sweaty sock at the end of my run today!

A marbled white butterfly (white wings with light grey markings) sat on a white sock.

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Mike Jacobs @mikejacobs.bsky.social · 02/07/2026

Try this shady #yohaku. Fill in cells with 9 different integers to get products shown in each row/column AND sum of 4 shaded cells is -3. #mathsky #iTeachMath

Use 9 different integers in a 3 by 3 grid. The numbers in the top row multiply to 52. The numbers in the middle row multiply to 105. The numbers in the bottom row multiply to 66. The numbers in the left column multiply to -78. The numbers in the middle column multiply to -14. The numbers in the right column multiply to 330. The sum of the integers in the 2 by 2 square at the top left of the grid is -3.

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