Problem:
How many three-digit numbers are divisible by
Answer Choices:
A.
B.
C.
D.
E.
Solution:
The smallest three-digit number divisible by is , so there are seven two-digit multiples of . The greatest three-digit number divisible by is . Therefore, there are three-digit numbers divisible by .
Because the integer part of is , there are multiples of less than or equal to . Because the integer part of is , there are multiples of less than or equal to . That means there are multiples of between and .
Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions