SOLUTION: Jenny runs 4 miles in 30 minutes. At the same rate, how many miles would she run in 18 minutes?

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Question 221219: Jenny runs 4 miles in 30 minutes. At the same rate, how many miles would she run in 18 minutes?
Found 2 solutions by rapaljer, RAY100:
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
Set up the proportion (or ratio!) %284+miles%29%2F%2830+min%29=%28x+mi%29%2F%2818+min%29

Since a%2Fb=c%2Fd means ad=bc,

%284+miles%29%2F%2830+min%29=%28x+mi%29%2F%2818+min%29 means that 4%2A18=30%2Ax
72=30x
x=72%2F30=2.4 mi.

R^2

Answer by RAY100(1637) About Me  (Show Source):
You can put this solution on YOUR website!
Remember velocity = Distance / Time,,,or v=d/t,,,or t= d/v,,,or d=v*t
.
v= 4 miles / (30 min * 1hr / 60 min )= 8 mph
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d= (18 min * 1 hr/60min) * 8 mph = 2.4 miles
.
check,,,,,4mi/ x = 30 min/ 18,,,,4*18/30 = 2.4,,,,ok
.