1998 Pascal Problem 22

A deck of 100 cards is numbered from 1 to 100. Each card has the same number printed on both sides. One side of each card is red and the other side is yellow. Barsby places all the cards, red side up, on a table. He first turns over every card that has a number divisible by 2. He then examines all the cards, and turns over every card that has a number divisible by 3. How many cards have the red side up when Barsby is finished?

\textbf{(A)}\ 83\quad \textbf{(B)}\ 17\quad \textbf{(C)}\ 66\quad \textbf{(D)}\ 50\quad \textbf{(E)}\ 49

If there are no answer choices shown, enter a numerical answer.

Full credit to this problem is given to the CEMC, you may view all Pascal contests here.