. . . involves repeated subtraction, but can you solve it?
Starting at 100, keep on subtracting 7 until you hit a 2-digit number that has both its digits the same. What is this number?
The 7puzzle Challenge
The playing board of the 7puzzle game is a 7-by-7 grid containing 49 different numbers, ranging from 2 up to 84.
The 1st & 7th columns of the playing board contain the following fourteen numbers:
5 9 13 21 22 24 27 28 32 50 55 56 60 66
Which two numbers, when 9 is added to each, become square numbers?
. . . can be found when clicking this.