Question

Mr Thomas's monthly expenditure was £2125 after

he had reduced it by 15%. The original monthly
expenditure was 80% of his monthly income. Find
(a) the original monthly expenditure,
(b) his monthly income.

Answer 1

a. £2,500

b. £3,125

Explanation:

The computation is shown below:

a. The original monthly expenditure is

Let us assume the original monthly expenditure be x

Monthly expenditure = x -15% of x

£2,125 = x - 0.15x

£2125 = 0.85x

x = £2125 ÷ 0.85

= £2,500

b. Now the monthy income is

Let us assume the monthly income be y

£2,500 = 80% of monthly income

£2,500 = 80% of y

y = £2,500 ÷ 80%

= £3,125