Question 109146
1st pipe fills 1/10 the pool  in 1 hr
2nd pipe fill 1/6 the pool in 1 hr
Together: 1/10 + 1/6
=3/30 + 5/30
=8/30
=4/15 of the pool filled in 1 hr or:
15/4= hrs until pool filled
= 3 3/4 hrs
= 3.75 hrs
.
and
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st=d, s=speed, t=time, d=distance
Let x be speed of the wind
t(280+x)=725
t=725/(280+x)
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t(280-x)=675
t=675/(280-x)
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Since the t's are equal:
725/(280+x)=675/(280-x)
725(280-x)=675(280+x) multiply both sides by (280-x)(280+x) to eliminate fractions.
203000-725x=189000+675x
14000=1400x add 725x-189000 to each side.
x=10 mph wind speed
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Check:
t=725/290=2.5 hrs
t=675/270=2.5 hrs
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Ed