Maths Topic 10 - Money & cost calculations


The solving of money sums is a skill that is commonly tested in 11+ exams and Selective School exams in the UK.

Examples

Example Question 1:

If 5 people have a pizza meal that costs £17.50, what would be the cost for 3 people to have the same meal?

Answer: £10.50

Explanation: The cost of one pizza meal is £17.50 ÷ 5 = £3.50. Multiply the cost of one meal by 3 people = £10.50

Example Question 2:

(a) If £1 = €1.50, how many € will you receive if you exchange £32?

(b) If £1 = €1.50, how many £ will you receive if you exchange €90 ?

Answers: (a) €48, (b) £60

Explanations: 

(a) Multiply the £ by the exchange rate of €1.50  → 32 × 1.5   = 48

(b) Divide the € by the exchange rate of €1.50 → 90 ÷ 1.5 = 60

Example Question 3:

Which packet of cereal is the best value: (A) 750g = £1.00, (B) 1kg = £1.25, (C) 400g = 80p?

Answer: Packet B

Explanation: Calculate the unit cost per gram: A = 750g ÷ 100p = 7.5g per pence , B =1000g ÷ 750p = 8g per pence, C = 400g ÷ 80p = 5g per pence. You receive more weight per pence of packet B which makes it the best value.

Multiplication of money video:

Changing £ to pence and pence to £ video:

Finding the cost of one item (unit cost):

Currency conversions