Help?

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?

How do I solve this?

Question

Help? 

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?

How do I solve this?

anonymous · Answer

nvm sorry i misread

anonymous · Answer

let the distance be x
average speed = total distance/total time = 2x/12 = 20 mph
therefore x = 120 miles

anonymous · Answer

i think i read wrong total time is not 12 hrs.

anonymous · Answer

So if he can go 20 mph out, that's 6 hours out... and  30 mph back, that's 4 hours back?

anonymous · Answer

well, no, because that's only 7 hrs..

anonymous · Answer

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? 
:
Let d = dist traveled one way
Write a time equation; time = dist/speed
d/20+d/30  = 12

 
multiply eq by 60, results
3d + 2d = 60(12)
5d = 720
d = 720/5 = 144 mi one way
:
Find the time at each speed
 144/20= 7.2 hrs at 20 mph
144/30 =4.8 hrs at 30 mph

Does this work?

anonymous · Answer

That helps a lot!

anonymous · Answer

distance coming back = 30mph x 12 hrs = 360 miles

anonymous · Answer

I am not going to plagerize....here is the site i found it from http://www.algebra.com/algebra/homework/word/travel/Travel_Word_Problems.faq.question.315526.html

anonymous · Answer

I needed a refresh in this anyways...thnx

anonymous · Answer

Thanks for the integrity @Mpost1994

anonymous · Answer

No problem