A two digit number is such that the product of the digits

is 8. When 18 is added to the number, the digits are
reversed. Find the number.

1 answer

Your choices are quite limited.
Since the digits have to be whole numbers, and
8 = 1x8 or 2x4

only 4 choices for the first condition are:
18, 81, 24, or 42

Which of these also matches the second condition of your problem?