2018 AMC 10A Problem 2

Below is the professionally curated solution for Problem 2 of the 2018 AMC 10A, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2018 AMC 10A solutions, or check the answer key.

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Concepts:percentageratio and proportion

Difficulty rating: 770

2.

Liliane has 50%50\% more soda than Jacqueline, and Alice has 25%25\% more soda than Jacqueline. What is the relationship between the amounts of soda that Liliane and Alice have?

Liliane has 20%20\% more soda than Alice.

Liliane has 25%25\% more soda than Alice.

Liliane has 45%45\% more soda than Alice.

Liliane has 75%75\% more soda than Alice.

Liliane has 100%100\% more soda than Alice.

Solution:

Let xx be the number of gallons of soda that Jacqueline has. Then Alice has 1.25x1.25x gallons, and Liliane has 1.5x1.5x gallons.

Therefore, the relationship can be found by dividing the amount of soda that each has to yield 1.5x1.25x=1.2,\dfrac{1.5x}{1.25x} = 1.2, which mean Liliane has 20%20\% more soda.

Thus, A is the correct answer.

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