Math Puzzle Answer

This is the solution to one of our math puzzles. We have several other puzzles to try to solve. Please click to see all our math puzzles.

Upside Down Calculator - Answer

The original number displayed was 9,126. Suzie saw 9,216 when it was turned upside down, or the square of 96.

When Glen multiplied the number by 2 he got 18,252, Suzie saw it as 25,281 when she turned it upside down - the square of 159.

The digits 0, 1, 2, 5, 6, 8, and 9 are all digits when they are looked at upside down. All of them appear as the same number except 6 and 9 which are reversed.

Make a list of all the squares that don't contain a 3, 4 or 7 or end in 0. Convert them to their upside down values, double them and discard those that contain a 3, 4, or 7. Convert those remaining to their upside down values and take the square root of each. The number 9,216 is the only integer which works and fits on a seven digit calculator.