The correct answer is 8. See the steps below:
1. We will use x for the unknown number.
2. X^2+24=5x according to the given info.
3. Move everything to one side.
X^2-5x-24=0
(X-8)(x+3)=0
X is 8 or -3.
However, the problem said positive number. So we can ignore the -3, the correct answer is 8.