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Guest Message by DevFuse

not so easy Math Problem

10 replies to this topic

#1 Barcallica

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Posted 07 June 2012 - 02:03 PM

A truck travels from A to B.

Going uphill, it goes at 56 mph.
Going downhill, it goes at 72 mph.
On level ground, it goes at 63 mph.
If it takes 4 hours to travel from A to B, and 5 hours to come back,
what is the distance between A and B?

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#2 kevink2

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Posted 07 June 2012 - 02:51 PM

Edited by kevink2, 07 June 2012 - 02:52 PM.

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#3 Potok

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Posted 07 June 2012 - 02:55 PM

Same answer here, is ofc correct.
Spoiler for the formula for the downhill

Edited by Potok, 07 June 2012 - 02:57 PM.

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#4 Barcallica

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Posted 07 June 2012 - 03:10 PM

Same answer here, is ofc correct.

Spoiler for the formula for the downhill

turned out to be so easy I guess. well done
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#5 CaptainEd

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Posted 07 June 2012 - 04:03 PM

Interesting! I got the same answer...,
Spoiler for ...but a different terrain profile.

Edited by CaptainEd, 07 June 2012 - 04:10 PM.

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#6 Potok

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Posted 07 June 2012 - 04:22 PM

So in your solution A is lower (compared to sea level) than B and you travel from A to B mostly uphill ? But the path from A to B is (timewise) shorter than from B to A.
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#7 superprismatic

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Posted 07 June 2012 - 06:55 PM

Spoiler for a little bit of explanation

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#8 CaptainEd

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Posted 07 June 2012 - 10:02 PM

So in your solution A is lower (compared to sea level) than B and you travel from A to B mostly uphill ? But the path from A to B is (timewise) shorter than from B to A.

Oops, you're right, I got it backward.
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#9 ujjagrawal

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Posted 08 June 2012 - 07:55 AM

Here is one way to solve this...
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#10 ujjagrawal

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Posted 08 June 2012 - 07:56 AM

x/63 + y/72= 4
x/63 + y/56= 5

x = 31.5 Mi ; net ground level distance.
y = 252 Mi ; net inclined distance

Total x + y = 283.5 Mi.
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