Question

Dan and Joan were able to dig a garden in 6 hours together. It takes

Joan 7 hours to complete this job alone. Without help, how long
would it take Dan to complete this job?

Answer 1

Explanation:

Let's assume that Dan takes x hours to complete the job alone.

Working together, Dan and Joan can complete the job in 6 hours. Therefore, their combined work rate is:

1 job / 6 hours = (1/x job/hour) + (1/7 job/hour)

Simplifying this equation, we get:

1/6 = (7+x)/7x

Multiplying both sides by 7x, we get:

x + 7 = 42

Therefore, x = 35 hours.

This means that Dan would take 35 hours to complete the job alone.