Maria drove to the mountains last weekend. There was heavy traffic on the way there, and the trip took 9 hours. When Maria drove home, there was no traffic and the trip only took 4 hours. If her average rate was 40 miles per hour faster on the trip home, how far away does Maria live from the mountains?  Choose the correct choice
A) 787 miles	B) 772 miles	C) 287 miles	D) 979 miles	E) 288 miles
Explanation:   Time taken for trip from home to mountains = 9 h   Time taken for trip from mountains to home = 4 h   Let distance from home to mountains = x miles   let avg speed from home to mountains = y miles/h   Given avg speed on the trip home is 40 m/h faster than speed from home to mountains = y + 40 m/h   ⇒ (x/9) = y and (x/4) = y + 40   by solving this, we get y = 32 m/h and the distance x=32 × 9 = 288 miles.   Answer:288 miles
<result>E</result>
Maria drove to the mountains last weekend. There was heavy traffic on the way there, and the trip took 9 hours. When Maria drove home, there was no traffic and the trip only took 4 hours. If her average rate was 40 miles per hour faster on the trip home, how far away does Maria live from the mountains?