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Tom drives 200 miles in 4 hours, he drives the first 32 miles at an average speed of 64mph, work out his average speed for the rest of the journey.

User Yan Zhou
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1 Answer

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Answer: Tom's average speed for the rest of the journey = 48mph

Explanation:

Total distance driven = 200 miles

total time taken = 4hours

first 32 miles , he drove at an average speed of 64mph, To find the amount of time taken for the first 32 miles,

We Use the formulae

Speed = distance / time

Time = Distance / speed

=32/64 = 1/2 =0.5 hours

The remaining distance = Total distance covered - first 32 miles covered

= 200 -32= 168 miles

The remaining time for rest of journey = Total time taken - time covered in the first 32miles

4hours - 0.5 hours

=3.5 hours

Therefore Average speed for the rest of the journey = Distance for the remaining journey/ remaining time

168miles/ 3.5hours = 48mph

User Jonathan Wright
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