Problem:
The number has the property that it is divisible by its units digit. How many whole numbers between and have this property?
Answer Choices:
A.
B.
C.
D.
E.
Solution:
Twelve numbers ending with , or have this property. They are , and . In addition, we have , and , for a total of . (Note that , and are not divisible by , since division by is not defined.)
Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions