distance problem: Graham walked school average speed....

[n0limit5]

Graham walked school average speed 3 miles hour jogged back along same route 5 miles hour. If his total traveling time was 1 hour, what was total number miles round trip

this is a SAT question and when i tried to do it i got 4 but the textbook claims 4 is not the answer and it doesnt tell me the answer to this question......Im not sure how to get started

 

[stapel]

Graham walked [to] school [at an] average speed [of] 3 miles [per] hour[, and] jogged back along [the] same route [at] 5 miles [per] hour. If his total traveling time was 1 hour, what was [the] total number [of] miles [for the] round trip[?]

Was what you posted really the way the exercise is written? With omitted prepositions and punctuation and such...? (I have inserted, above, clarification of my interpretation of what is meant, but there may be other, equally valid, interpretations.)

when i tried to do it i got 4...

Please reply showing what you did, according to your understanding of the exercise. Thank you.

Eliz.

 

[n0limit5]

Was what you posted really the way the exercise is written?

Sorry about that i typed down key words for my friend to help me with and then i copied and pasted this on the forum. This is what it says:

• Graham walked to school at an average speed of 3 miles an hour and jogged back along the same route at 5 miles an hour. If his total traveling time was 1 hour, what was the total number of miles in the round trip?

My friend couldn't help me solve it and i can't find an equation.

 

[Denis]

basic formula: speed = distance / time : s = d/t : so t = d/s

walking: t = d/3
jogging: t = d/5

d/3 + d/5 = 1

Can you finish it?

 

[n0limit5]

Thanks man, that simple formula made me feel pretty stupid...=)

 

[n0limit5]

hrm i look in my SAT book again and the only answer choice for this problem is 3, 3 1/8, 3 3/4, 4, and 5.... i got 15/8=1 7/8

 

[stapel]

Please reply showing all of your steps (everything between the set-up and equation, which were provided by the tutor, and your final answer). Thank you.

Eliz.

 

[Denis]

hrm i look in my SAT book again and the only answer choice for this problem is 3, 3 1/8, 3 3/4, 4, and 5.... i got 15/8=1 7/8

1 7/8 is correct as the 1way distance: but this distance was covered TWICE:
so (15/8) * 2 = 30/8 = 15/4 = 3 3/4 : give yourself a good kick :shock:

 

[n0limit5]

OMG LOL im feeling dumb thanks for helping it was a "hard problem" according to SAT book and me lol.