Answer:
Lily is 6.
Explanation:
The factors of 24 are: 1, 2, 3, 4, 6, 8, 12, 24.
The expressions that makeup these factors are: 1 x 24, 2 x 12, 3 x 8, 4 x 6.
Their ages must be the two numbers in one of these expressions, the one with a value two more than the other would be 4 x 6 and since Lily is the older she is 6.