#16
+8 Numbers ending in zero are the obvious case, now let´s solve the other cases
Let the variable n represent the new number you get after cutting off the last digit.
Let the variable d represent the last digit.
The original number is (10*n)+d
the problem says the original number is divisible by n
which means (10*n)+d is divisible by n
((10*n)+d)/n = 10 + d/n
that means d must be a multiple of n
for example, try the number 24
4 is a multiple of 2, so it works. Check it
cut off 4, the new number is 2, which divides into 24
11, 12, 13, 14, 15, 16, 17, 18, 19, 22, 24, 26, 28, 33, 36, 39, 44, 48, 55, 66, 77, 88, 99 all work
and of course any number ending in 0
so it looks like we are limited to two-digit numbers and numbers ending in 0
