2012 AMC 10A Problem 5

Below is the professionally curated solution for Problem 5 of the 2012 AMC 10A, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2012 AMC 10A solutions, or check the answer key.

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Concepts:fractionmean

Difficulty rating: 870

5.

Last year 100100 adult cats, half of whom were female, were brought into the Smallville Animal Shelter. Half of the adult female cats were accompanied by a litter of kittens. The average number of kittens per litter was 4.4. What was the total number of cats and kittens received by the shelter last year?

150150

200200

250250

300300

400400

Solution:

We have that there are 100÷2=50100 \div 2 = 50 female cats. We then have that 50÷2=2550 \div 2 = 25 cats that have kittens.

Since the average number of kittens per litter is 4,4, the total number of kittens is 425=100. 4 \cdot 25 = 100.

The total number of cats and kittens is then 100+100=200. 100 + 100 = 200.

Thus, B is the correct answer.

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