Math Puzzle for February 13, 2026

‘Love may make the world go around, but oil lubricates the axle.’

Alameda Post - A diagram of a sand conveyer belt.

To automate his sand castle project, Tristan rented an AI-guided sand conveyor. At redline speed, it sifted, sorted, and piled Crab Cove sand into a perfect cone. After the conveyor operated for just five minutes, the cone of sand stood 3 feet tall.

If the shape remains constant, find the total time T until the cone reaches 9 feet high.

Send the correct answer to [email protected] for a chance to win a Tucker’s gift card.

Last week’s winner was James Forakis with diameter D = 130 meters.

(Extra credit: Given: yz = x and 8z = xy and y = ½ z, find the value of z.)

Jeff Smith is a former Math teacher and a retired US Navy Lieutenant Commander. Reach him at [email protected].

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