1. The Water Bill Steps to tackle the task

2. Nia lives on her own in a flat in Wrexham, and is trying to manage her budget. She is currently paying £15.65 a month on her water bill, and wants to know if this would be lower if she had a water meter. She tries to estimate her current water usage. She uses the shower every day. The toilet is flushed 4 times a day. The washing machine is used twice a week.

3. The water company gives her a leaflet with this table to show how much each appliance uses: From this table she estimates using 35 litres a day for washing, cooking, cleaning, drinking water, washing up, and brushing her teeth.

4. If Nia changed to a water meter, the charges would be: Standing charge (for a year): £28.95 Water charges: £1.53 per cubic metre. She knows that 1000 litres = 1 cubic metre. How much a month would Nia save if she switched to a meter?

5. What is the question/instruction? Highlight it. How much a month would Nia save if she switched to a meter?

6. What information am I given? (Highlight if necessary) We have information about her water usage, and the cost of water.

7. What information/results do I need to solve the problem? We need to find out exactly how much water she uses in a week, and then a year in cubic metres, then multiply that by the cost (£1.53) per cubic metre, and then add that to the standing charge. We then need to change that to a monthly charge, in order to find how much less she would pay per month.

8. How can I use the information I have? Can I simplify, extend, reorganise or represent the information to help solve the problem? Firstly calculate the water usage in the week, using the table and her own estimate. Her estimate already uses some information in the table, so we do not have to use it again. Then multiply that by a year, and change to cubic metres, because the information we have is in litres. Calculate usage for each week first, then for a year. Calculate the annual charge, then the charge per month. Then we have to find the difference between what she would pay and what she pays now.

9. What mathematics will we use? Multiplication, division, addition, subtraction

10. What do our results tell us? How are we checking if our results are sensible?

11. How should we present our findings? Litres, cubic metres, pounds and pence

12. Evaluate our work Have we answered the question?

13. Can we extend the question? E.g. what is our water usage? One water company suggests that the average water usage is 145 litres per person per week. How does Nia’s usage compare?