SOLUTION: In a race the top speed of one car is 9/10 of the top speed of a another. After one half hour faster car is 10 km ahead of the slower car find the rate of each car assuming they st

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Question 977156: In a race the top speed of one car is 9/10 of the top speed of a another. After one half hour faster car is 10 km ahead of the slower car find the rate of each car assuming they started side-by-side.
Answer by ankor@dixie-net.com(22740) (Show Source):
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In a race the top speed of one car is 9/10 of the top speed of a another.
After one half hour faster car is 10 km ahead of the slower car.
find the rate of each car assuming they started side-by-side.
:
let s = speed of the faster car
then
.9s = speed of the slower
;
Write a distance equation; dist = speed * time, use .5 hrs for travel time
.5s = .5(.9s) + 10
.5s = .45s + 10
.5s - .45s = 10
.05s = 10
s = 10/.05
s = 200 km/hr is the speed of the faster car
then
.9(200) = 180 km/hr is the speed of the slower
:
:
Confirm this, find the actual dist each traveled
200*.5 = 100 km
180*.5 = 90 km
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dist dif: 10 km