Question

A mayor wants to reduce traffic congestion, and so imposes a rule that each car owner must pick two days out of seven days that the car will not be used. A business owner needs 10 cars on the road each day to complete company work. How many cars must the owner have in his possession?

Answer 1

To determine the number of cars the business owner must have in his possession, we need to consider the mayor's rule and the business owner's requirement.

According to the mayor's rule, each car owner must pick two days out of seven days that the car will not be used. This means that for any given day, the business owner can only have 5 cars on the road, as 2 cars are not being used.

To meet the business owner's requirement of having 10 cars on the road each day, the owner would need to have enough cars to cover the days when some cars are not being used.

Since 2 cars are not being used on any given day, the owner would need to have an additional 2 cars for each day. Therefore, the business owner would need a total of 12 cars in his possession.

This is because having 12 cars would allow the owner to have 10 cars on the road each day, even when 2 cars are not being used.

So, to reduce traffic congestion and meet the business owner's requirement of having 10 cars on the road each day, the owner must have a total of 12 cars in his possession.

Answer 2

The answer is 14.

Explanation:

Each car is not used for 2 days a week, which means each car is used for 5 days a week.

The business owner needs 10 cars on the road each day.

So, if we let x be the number of cars the business owner needs to have, we can set up the following equation:

5x=10×7

Solving for x gives us:

x=510×7​=14

So, the business owner must have 14 cars in his possession.