2013 AMC 12A Problem 3

Below is the professionally curated solution for Problem 3 of the 2013 AMC 12A, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2013 AMC 12A solutions, or check the answer key.

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Concepts:fractionpercentage

Difficulty rating: 1100

3.

A flower bouquet contains pink roses, red roses, pink carnations, and red carnations. One third of the pink flowers are roses, three fourths of the red flowers are carnations, and six tenths of the flowers are pink. What percent of the flowers are carnations?

1515

3030

4040

6060

7070

Solution:

Six tenths of the flowers are pink and four tenths are red. Since two thirds of the pink flowers are carnations, pink carnations make up 23610=410\tfrac{2}{3}\cdot\tfrac{6}{10} = \tfrac{4}{10} of the flowers.

Since three fourths of the red flowers are carnations, red carnations make up 34410=310\tfrac{3}{4}\cdot\tfrac{4}{10} = \tfrac{3}{10} of the flowers. Together the carnations are 410+310=710=70%.\tfrac{4}{10} + \tfrac{3}{10} = \tfrac{7}{10} = 70\%.

Thus, the correct answer is E.

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