Please help a.s.a.p!!! Word problem Alg. 1 Honors

zenbassism

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Sep 14, 2011
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Hi all!

Here's the problem: "Albert traveled from Santa Cruz to San Francisco at a rate of 60 miles per hour and returned from San Francisco to Santa Cruz at a rate of 40 miles per hour. Find Albert's average rate for the entire trip." -thank you! K (p.s. according to my math teacher, the answer was not 50 mph)
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"Albert traveled from Santa Cruz to San Francisco at a rate of 60 miles per hour and returned from San Francisco to Santa Cruz at a rate of 40 miles per hour. Find Albert's average rate for the entire trip." -thank you! K (p.s. according to my math teacher, the answer was not 50 mph)

Hello, Zen,

You need to do a little work/show some effort to let us know where you are stuck.

Forget about the info supplied in the problem for a second and ask yourself what "average rate" means. If the problem had been different, and merely stated the TOTAL amount of TIME and the TOTAL DISTANCE covered, how would you have solved for the AVERAGE RATE? Simple problem, right? Apply that same principle to your problem. (PS I suspect you were given the distance between SF and SC -- which you failed to tell us -- but which is necessary to solve the problem. If that distance was not supplied, you'll have to look it up.)

Hope that helps.
 
Following WJM's suggestion:

Assume the distance between SF and SC = d

Time to travel from SC to SF = d/60

Time to travel from SF to SC = d/40

Total time of travel = d/60 + d/40

Total distance travelled = d + d = 2*d

Average speed = 2*d/(d/60 + d/40) = simplify ....
 
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