It took John 12 hours riding his bike to make the round trip to his uncle's. If he averaged 20 mph out and 30 mph back, how long did he travel each way? (Round answer to nearest tenth.)

Question

anonymous · Answer

if d is distace...then time taken 
t1=d/20 and t2= d/30
now t1+t2=12
d/20+d/30 = 12
d(1/20 +1/30)=12
d=144 m

anonymous · Answer

The distance remains the same. (12 - A) * 20 = (12 - B) * 30 The total time remains the same: A + B = 12 http://www.wolframalpha.com/input/?i=%2812-A%29*20+%3D+%2812-B%29*30+%26+A+%2B+B+%3D+12

anonymous · Answer

ok how many hours did he go each way?

anonymous · Answer

7.2 and 4.8

anonymous · Answer

144/20 =7.2
144/30=4.8