2015 AMC 10A Problem 4

Attempt Problem 4 of the 2015 AMC 10A below, then check your answer against the professionally curated solution from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2015 AMC 10A solutions, or check the answer key.

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4.

Pablo, Sofia, and Mia got some candy eggs at a party. Pablo had three times as many eggs as Sofia, and Sofia had twice as many eggs as Mia. Pablo decides to give some of his eggs to Sofia and Mia so that all three will have the same number of eggs. What fraction of his eggs should Pablo give to Sofia?

112\dfrac{1}{12}

16\dfrac{1}{6}

14\dfrac{1}{4}

13\dfrac{1}{3}

12\dfrac{1}{2}

Answer: B
Concepts:ratio and proportionfraction
Difficulty rating: 1020
Small Hint:

Write Mia, Sofia, Pablo as m,2m,6mm,2m,6m

Big Hint:

Equal sharing means each person ends with 3m3m eggs

Solution:

Let mm be the number of candy eggs that Mia had. Then Sofia had 2m2m eggs and Pablo had 6m6m eggs.

The total number of eggs is then m+2m+6m=9m. m + 2m + 6m = 9m. For all of them to have the same number of eggs, they each must have 9m÷3=3m9m \div 3 = 3m eggs.

Sofia needs 3m2m=m3m - 2m = m more eggs. This means Pablo must give m6m=16\dfrac{m}{6m} = \dfrac{1}{6} of his eggs to Sofia.

Thus, B is the correct answer.

Problem 3#3
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