Question

a knife is four times the cost of a spoon. 12 spoons and 16 knives cost £105.64. work out the cost of 1 knife

Answer 1

Answer:

£5.56

Step-by-step explanation:

let K be the cost of a knife

    S Ben the cost of a spoon

The statement “a knife is four times the cost of a spoon”

means  K = 4S

means  S = (1÷4)K

the statement “12 spoons and 16 knives cost £105.64”

means  12S + 16K = 105.64

⇔ 12(1÷4)K + 16K = 105.64

⇔ 3K + 16K = 105.64

⇔ 19K = 105.64

⇔ K = 105,64÷19

       = £5.56