30 yrs old
Explanation:
The factors of 60 are 1 and 60, 2 and 30, 3 and 20, 4 and 15, 5 and 12, and 6 and 10.
The next clue eliminates every number except 5, 10, 15, 20, 30, and 60.
5, 10, 15 are less than 20 and eliminated (60 is eliminated because it is more than 50).
20 is eliminated because it is not greater than itself and so Mrs. Smith must be 30.
There are 12 inches in a foot and 3 feet in a yard
so you multiply 110 by 3 to get the number of feet, which is 330
and then you multiply 330 by 12 to get the total number of inches.
The answer is 3960 inches.
