# The Davis family try shopping in a different supermarket to save money.

They used their old supermarket one week, then bought the same items the next week in the new supermarket.

In the first week their bill was £105.20. In the second week it was £98.50.

a) What was the change in their bill?

b) Use the first bill and you answer to part a to work out the percentage decrease.

I know the answer to a is £6.70 but I don't know the method to b. Any help please?

Sorry if you don't know the british currency. Hopefully you can still work it out.

Thank you.

## a) Subtract.

b) Divide the difference by the first week's bill.

## To calculate the percentage decrease, you need to find the percentage change between the two bills.

a) The change in their bill is £105.20 - £98.50 = £6.70.

b) To find the percentage decrease, divide the change in their bill (£6.70) by the original bill amount (£105.20), and then multiply by 100:
(£6.70 / £105.20) * 100 = 6.36%

Therefore, the percentage decrease in their bill is approximately 6.36%.