Question

Solve the following problems by writing a proportion. 8 is 40% of what number?

Answer 1

Let x be the number

40% of x = 8

`(40)/(100)* x=8`
`(40x)/(100)=8`

Multiply both-side of the equation by 100

`40x\text{ = 800}`

Divide both-side of the equation by 40

`x=20`

Therefore, 8 is 40% of 20