2020 AMC 10A Problem 1

Below is the video solution and professionally curated solution for Problem 1 of the 2020 AMC 10A, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2020 AMC 10A solutions, or check the answer key.

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Concepts:fractionlinear equation

Difficulty rating: 560

1.

What value of xx satisfies x34=51213?x- \frac{3}{4} = \frac{5}{12} - \frac{1}{3}?

23\displaystyle -\frac{2}{3}

736\displaystyle \frac{7}{36}

712\displaystyle \frac{7}{12}

23\displaystyle \frac{2}{3}

56\displaystyle \frac{5}{6}

Video solution:
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Written solution:

The right side is 51213=512412=112\dfrac{5}{12}-\dfrac13=\dfrac{5}{12}-\dfrac4{12}=\dfrac1{12}. Thus x=34+112=912+112=56x=\dfrac34+\dfrac1{12}=\dfrac9{12}+\dfrac1{12}=\dfrac56. Thus, E is the correct answer.

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