Question

A tennis player hits a serve that cannot be returned 45% of the time. Out of 300 serves, how many can the tennis player predict will not be returned?

Answer 1

See a solution process below:

Explanation:

We can restate this problem as:

What is 45% of 300.

"Percent" or "%" means "out of 100" or "per 100", Therefore 45% can be written as `45/100`.

When dealing with percents the word "of" means "times" or "to multiply".

Finally, lets call the number of serve that cannot be returned we are looking for "s".

Putting this altogether we can write this equation and solve for `s` while keeping the equation balanced:

`s = 45/100 xx 300`

`s = 45 xx 3`

`s = 135`

The tennis player would predict 135 serves would not be able to be returned.