SOLUTION: This is a very simple formula but I can not make it work with this problem - D=RT
The word problem is from a handout on Polynomils
"Jamie ran two laps around a track in 99s. How
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-> SOLUTION: This is a very simple formula but I can not make it work with this problem - D=RT
The word problem is from a handout on Polynomils
"Jamie ran two laps around a track in 99s. How
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Question 160912: This is a very simple formula but I can not make it work with this problem - D=RT
The word problem is from a handout on Polynomils
"Jamie ran two laps around a track in 99s. How long did it take him to run each lap if he ran the first lap at 8.5m/s and the second at 8.0 m/s?"
my break down
D1=R1T1 1 lap=8.5m/sT but I don't know how many miles my lap is?
d2=R2T2 1 lap=8.0m/sT
I am stuck - thank you Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Jamie ran two laps around a track in 99s.
distance = 2D; t= 99s ; rate = d/t = 2D/99 meters/second
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How long did it take him to run each lap if he ran the first lap at 8.5m/s and the second at 8.0 m/s?"
1st lap DATA:
distance = D ; rate = 8.5 m/s; time = D/8.5 seconds
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2ns lap DATA:
distance = D ; rate = 8.0 m/s ; time = D/8 seconds
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EQUATION:
time + time = 99 seconds
D/8.5 + D/8 = 99
8D + 8.5D = 99*8.0*8.5
Using 8.0 and 8.5 because that is the least common multiply of the denominators.
16.5D = 6732
D = 408 meters
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Time for 1st lap: time = distance/rate = 408/8.5 = 48 seconds
Time for 2nd lap: time = distance/rate = 408/8 = 51 seconds
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Cheers,
Stan H.
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