Question

Loft insulation reduces annual heating costs by 20%. After he insulated his loft, curtleys annual heating cost was £520. Work out curtleys annual heating cost would have been, if he had not insulated his loft.

Answer 1

520 x 0.2 = 104
520 + 104 = 625
Curtley's annual heating cost before he got his loft insulated was $624.00

Answer 2

$650

Explanation:

Let x represent curtleys original annual heating cost.

We have been given that Loft insulation reduces annual heating costs by 20%.

So the cost after 20% reduction would be 80% of original cost that is
`(80)/(100)x=0.80x`.

We have been given that after he insulated his loft, curtleys annual heating cost was £520. We can represent this information in an equation as:

`0.80x= \$520`

`(0.80x)/(0.80)= (\$520)/(0.80)`

`x=\$650}`

Therefore, Curtley's annual heat costing would have been $650, if he had not insulated his loft.