Care to try a math problem that may be a little more difficult than it at first appears?

How many even numbers are there from 1 to 600 that are not divisible by 7?

If you are stuck, here is a way of looking at it. Imagine a Venn diagram for the numbers from 1 to 600. Draw circle A to represnt the even numbers from 1 to 600 and circle B to represent the numbers from1 to 600 that are divisible by 7. C = intersection of A and B, representing numbers from 1 to 600 divisible by both 2 and 7.

Suppose you knew the sizes of A and C. Do you see how to answer the problem? The size of A is easy to compute. How can you compute the size of C?
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