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BRO I NEED HELP!!!!

Two cars traveled equal distances in different amounts of time. Car A traveled the distance in 2 h, and Car B traveled the distance in 1.5 h. Car B traveled 15 mph faster than Car A. How fast did Car B travel?
(The formula R•T=D,where R us rate of speed, T is time, and D is the distance can be used) PLEASE HELP!!

User Bennyxguo
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1 Answer

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Let A represent the speed of car A. Using your formula,
.. A*2 = D
.. (A +15)*1.5 = D . . . . . the same distance in a shorter time at a higher speed

Equating the two expressions for D, we get
.. 2A = 1.5(A +15)
.. 2A = 1.5A +22.5 . . . . . eliminate parentheses
.. 0.5A = 22.5 . . . . . . . . .subtract 1.5A
.. A = 22.5/0.5 = 45 . . . .divide by 0.5
Car B was 15 mph faster than this.

Car B traveled at 60 miles per hour.
User Brad Barber
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