Functional Maths

Our school is closed on Wednesday 25th January due to work on the gas main. So as pupils don't miss out on vital learning here is a functional maths question to keep you occupied.

Mr Walker receives his gas bill every three months.

He pays £45 to the gas company every month.

The first 350 units of gas on each bill cost 7.2p per unit.

The rest of the units cost 4p.

Mr Walker gets a rebate of £41.64 for money he has overpaid in the last 3 months.

How many units of gas has Mr Walker used in the last three months?

Remember you need to show each step of your working and show all the sums that you have carried out.

Challenge

In order to install the new gas main a considerable amount of digging will need to take place. Can you come up with a solution to the following problem?

Working alone, Ryan can dig a 10 ft by 10 ft hole in five hours. Chris can dig the same hole in six hours. How long would it take them if they worked together? Give your answer in both hours (2 decimal places) and hours and minutes.