Question

Suppose that it takes Jenny 2 hours to wax a car if she works alone and it takes Carol 4 hours to wax the same car if she works alone. How long will it take them to wax the car, in hours, if they work together?

Answer 1

2 hours a the most I think

Answer 2

1 1/3

Explanation:

x

2

+

x

4

= 1

(4)

x

2

+ (4)

x

4

= (4)1

2x + 1x = 4

3x = 4

x =

4

3

= 1

1

3