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 Question from Gerry: A delivery driver travels from Belfast to an address in Dublin. The total distance for the round trip was x%.The time required for the forward trip was xx hours. Due to heavy traffic during the return trip an extra xx was required How much slower was the delivery drivers speed on the return trip? I was wondering what equation would you use to solve this question.

Hi Gerry,

A delivery driver travels from Belfast to an address in Dublin.The total distance for the round trip was 2d kilometres .The time required for the forward trip was f hours. Due to heavy traffic during the return trip an extra e hours was required. How much slower was the delivery drivers speed on the return trip?

I made the total distance 2d kilometers because I am assuming it is d kilometers each way.

Since distance = time rate I know that on the forward trip

rate = d/f kilometers per hour

The return trip took f + e hours so on the return trip

rate = d/(f + e) kilometers per hour

Thus the return trip was d/f - d/(f + e) kilometers per hour slower than the forward trip.

I hope this helps.
Penny

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