2017 AMC 12A Problems/Problem 13

Revision as of 14:55, 8 February 2017 by Speck (talk | contribs) (Created page with "==Problem== Driving at a constant speed, Sharon usually takes <math>180</math> minutes to drive from her house to her mother's house. One day Sharon begins the drive at her u...")
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

Problem

Driving at a constant speed, Sharon usually takes $180$ minutes to drive from her house to her mother's house. One day Sharon begins the drive at her usual speed, but after driving $\frac{1}{3}$ of the way, she hits a bad snowstorm and reduces her speed by $20$ miles per hour. This time the trip takes her a total of $276$ minutes. How many miles is the drive from Sharon's house to her mother's house?

$\textbf{(A)}\ 132 \qquad\textbf{(B)}\ 135 \qquad\textbf{(C)}\ 138 \qquad\textbf{(D)}\ 141 \qquad\textbf{(E)}\ 144$