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2 years ago

15

A boat in still water is 32 mph. If the boat travels 72 miles upstream in the same time that it takes to travel 120 miles downst

ream, find the speed of the current.

1 answer:

dalvyx [7]2 years ago

8 0

Dup= 72 miles
<span>ddown= 120 miles </span>
<span>v= riverspeed </span>
<span>rup= 32mph - v </span>
<span>rdown= 32mph + v </span>
<span>t both ways= t </span>

<span>d=r*t </span>
<span>d/r=t </span>

<span>t=ddown/rdown </span>
<span>t=dup/rup </span>

<span>dup/rup = ddown/rdown </span>

<span>(72)/(32-v)=(120)/(32+v) </span>
<span>3840-120v=2304+72v </span>
<span>1536=192v </span>
<span>v=8</span>

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