2014 AMC 12B Problem 2

Below is the professionally curated solution for Problem 2 of the 2014 AMC 12B, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2014 AMC 12B solutions, or check the answer key.

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Concepts:ratio and proportionmoney

Difficulty rating: 1070

2.

Orvin went to the store with just enough money to buy 3030 balloons. When he arrived he discovered that the store had a special sale on balloons: buy 11 balloon at the regular price and get a second at 13\tfrac13 off the regular price. What is the greatest number of balloons Orvin could buy?

3333

3434

3636

3838

3939

Solution:

Under the sale, a pair of balloons costs 1+23=531 + \tfrac23 = \tfrac53 times the regular price of one balloon.

Orvin's money buys 3030 balloons at the regular price, so he can afford 30÷53=18 30 \div \tfrac53 = 18 pairs, which is 3636 balloons.

Thus, the correct answer is C.

Problem 2 in Other Years