Question

Bob has 57 guests he wants to make sure everyone gets a slice of cake. One is 20cm at £13.50 and one 25cm at £18.75 he wants to pay as little as possible. How much will he have to pay

Answer 1

£56.25

Explanation:

Number of guest = 57

The 20cm cake :

Can serve 12 people and cost £13.50

The 25cm cake :

Can serve 20 people and cost £18.75

Since the cake has to be the same size, the only one particular size would have to be purchased ;

For the 20cm cake ; 57/12 = 4.75 = five 20cm cakes ;

£13.50 * 5 = £67.50

For 25cm cake ; 57 / 20 = 2.85 = three 25cm cakes

£18.75 * 3 = £56.25

£56.25 is lower ; hence, amount he'll have to pay is £56.25