Question #N404

A store sells two types of cookies: chocolate chip and peanut butter. On a particular day, the store sold 180 chocolate chip cookies. If the ratio of chocolate chip cookies to peanut butter cookies sold that day was 5:3, how many peanut butter cookies did the store sell?
A. 60
B. 90
C. 108
D. 180

Correct Answer is: C

The ratio 5:3 means that for every 5 chocolate chip cookies sold, 3 peanut butter cookies were sold. We can set up a proportion: \frac{5}{3} = \frac{180}{x}. Cross-multiplying gives 5x = 540. Dividing both sides by 5 gives $x = 108$.