ramona cycles from her house to school at 15mph and returns home at 25mph. if the entire trip takes 32 min, then what is the her avg speed, in miles per hour, for the entire round trip?

Question

anonymous · Answer

formula for avg. speed??

anonymous · Answer

not sure but are you referring to d=rt

anonymous · Answer

It is 5 miles each way:

5 miles / 15 miles per hr = 20 minutes

5 miles / 25 miles per hr = 12 minutes

Added, that gives you your 32 minutes.

Now, that is 10 miles in 32 minutes = 18.75 mph

anonymous · Answer

All good now, @lawls ?

anonymous · Answer

sorry but how'd you know where to start

anonymous · Answer

(x miles)/(1/4 miles per minute) = 4x = y minutes for the slow leg

(x miles)/(5/12 miles per minute) = 12x/5 = 32 - y minutes for the fast leg

(32 - y) +  y = 32 = 4x + 12x/5    ->    x = 5 miles

anonymous · Answer

The trick is to find the distance.

anonymous · Answer

okay thank you!

anonymous · Answer

uw!

anonymous · Answer

there you go

anonymous · Answer

uw!  Good luck to you in all of your studies and thx for the recognition! @lawls

anonymous · Answer

no problem and thanks :)