<PRE><B>Question 1133365</B>
two cars leave the same place at the same time traveling in the same direction for 3 hours.
 the first car travels twice as fast as the second car.
 how fast is the second car traveling if they are 90 miles apart when they stop?
:
let s = speed of the 2nd car
then
2s = speed of the 1st
:
write a distance equation, dist = speed * time
1st dist - 2nd car dist = 90 mi
2s(3) - s(3) = 90
simplify, divide equation by 3
2s - s = 30
s = 30 mph is speed of the 2nd car
:
:
Check this: find the actual distances each travels
60 * 3 = 180 mi for the 1st car
30 * 3 = 90 mi for the 2nd
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difference: 90 mi

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