Question

You buy the following materials for the new extension.

Answer 1

I assume you mean

2 tonnes of sand at £75.00 per tonne

20 bags of cement at £6.70 per bag

350 bricks at 45p each

If so, then

2 tonnes of sand at £75.00 per tonne = 2 * £75.00 = £150.00

20 bags of cement at £6.70 per bag = 20 * £6.70 = £134.00

350 bricks at 45p each = 350 * £0.45 = £157.50

Add the three amounts

£150.00 + £134.00 + £157.50 = £441.50

Answer: 441.50