Question

Question #be954

Answer 1

See below...

Explanation:

First lets make sure that the fractions have the same denominator, in this case `20`.

`therefore`

`2/5 * 4/4 = 8/20`
`1/4 * 5/5 = 5/20`

Together they have mowed `8/20 + 5/20 = 13/20`

Treat the whole lawn as `1` which is the same as `20/20`

`therefore 20/20 - 13/20 = 7/20`

Therefore `7/20` of the lawn still needs mowing.