Answer:

1. 1/x

2. x+3

3. 1/2

Explanation

To get the answer in number 1 we just divide work by hours and so we get 1/x

In number 2 we could get the answer by looking at mary's work rate it shows that

1/x+3 = work/hours which means x+3 = hours

In number 3 its pretty simple we just divide work by hours again which gets us 1/2

Brainliest would be much appreciated