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Two cars are 270 miles apart and travel toward each other on the same road. They meet in 3 hours. One car travels 2 mph faster than the other. What's the average speed of each car?

A. 42 mph and 44 mph
B.44 mph and 46 mph
C.41 mph and 43mph
D.43mph and 45mph

1 Answer

5 votes

Answer:

B.44 mph and 46 mph

Explanation:

This question is on relative speed

when cars move towards each other, you add their individual speeds to get their relative speed

Lets have two cars , A and B

Let car A to have an average speed of x m/h towards the right hand side

Let car B to have an average speed of x+2 m/h towards the opposite direction

The distance between the cars is 270 miles

Time of meeting is 3 hours

The relative speed will be x+x+2=2x+2 miles per hour

Apply the formula for time=Distance/speed =D/S


t=(D)/(S) \\\\\\3=(270)/(2x+2) \\\\\\3(2x+2)=270\\\\\\6x+6=270\\\\\\6x=270-6\\\\\\6x=264\\\\\\x=(264)/(6) =44

x=44 miles per hour

x+2=44+2=46 miles per hour

solution

44 mph and 46 mph

User Yves Boutellier
by
5.0k points
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