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For the first 30 km, the bicyclist rode with a speed of v km/hour. For the remaining 17 km he rode with a speed which was 2 km/hour greater than his original speed. How much time did the bicyclist spend on the entire trip? Let t be the time (in hours), and find t if:

2 Answers

3 votes

The question is incomplete. This is the complete question:

For the first 30 km, the bicyclist rode with a speed of v km/hour. For the remaining 17 km he rode with a speed which was 2 km/hour greater than his original speed. How much time did the bicyclist spend on the entire trip? Let t be the time (in hours), and find t if: v = 15

Answer:

The total time the bicyclist spent on the entire trip = T1 + T2 = 2 hours + 1 hour = 3 hours

Explanation:

For the first 30 km, the bicyclist rode with an original speed = 15 km/hour

For the remaining 17 km, the bicyclist rode with a speed = 15 + 2 = 17 km/hour

Generally, speed = distance ÷ time

Therefore, time = distance ÷ speed

The time spent on travelling the first distance of 30 km = T1 = 30 ÷ 15 = 2 hours

and the time spent on travelling the second distance of 17 km = 17 ÷ 17 = 1 hour

Therefore, the total time the bicyclist spent on the entire trip = T1 + T2 = 2 hours + 1 hour = 3 hours.

User RussF
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3 votes

If v = 15 km/h We have:

d1 = 30 km

d2 = 17 km

Since speed = distance/time follows time = distance/speed.

The total time of the entire trip is is the sum of the time of the first 30 km and the time of the remaining 17 km:

d1/v + d2/(v + 2) = 30/15 + 17/(15 + 2) = 2 + 1 = 3 hours

The answer is t=3hours

User Xcelled
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8.2k points