If eight pencils cost $0.42, how many pencils can be purchased with $2.10?

40, because you have to divide 2.10 by 0.42 and when you do so you get 5, then you multiply by 8 because 8 pencils cost 0.42.

I think the answer is (E) which is 40 because first you divide 2.10 by .42 which equals 5. Since you can get 8 pencils for .42 cents you just multiply 8 by 5.