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Question

My brother and I are going on vacation. We need to rent a car. We will rent the car for $10$ days. However, I will only be on the vacation for $5$ days. My brother will be on vacation for the full $10$ days. The cost of the car is $£600$. How much should he pay and how much should I pay?

Answer 1

You could think of this in terms of 'man-days' - one man-day is when one man is on holiday for one day. How many man-days are there in your holiday? Now try and share the cost of the car across all man-days and scale up according to how many man-days your and your brother each contribute.

Answer 2

You are paying $60$ for every day you own the car. For the first $5$ days, you pay $300$ and split the bill, meaning you pay $150$, for the second $5$ days, your brother pays the whole $300.$

Answer 3

You will be on vacation for 5 days, and your brother for 10. So the total amount of vacation days is 15. Split the price (600) over the number of days (15) to get 40 pounds per day. Therefore, you pay 200 while your brother pays 400.