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The distance from Charlotte to Asheville is about 120 miles. If R.C. has two hours to make the trip, but drives 50 mph for the first 60 miles, how fast must R.C. go on the second half of the trip to reach Asheville in time?

A. 70 mph
B. 75 mph
C. 77.2 mph
D. none of these

User Bhspencer
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2 Answers

6 votes
The answer is b

Hope it helps
User Nocturnal
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9 votes

Answer:

B. 75 mph

Explanation:

d - distance

v - velocity

t - time

d = 120 miles

t = 2 hrs

1st 60 miles :


v = (d)/(t)


t = (d)/(v)


t = (60)/(50)


t = 1.2 \: hrs


t = 1.2 * 60


t = 72 \: minutes

2nd 60 miles:

It took 72 minutes for him to travel the first 60 miles. To get the remaining time:


t = 120 - 72


t = 48 \: minutes


t = 0.8 \: hrs

For the Velocity:


v = (d)/(t)


v = (60)/(0.8)


v = 75 \: mph

User Votelessbubble
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4.5k points