The first person takes 9 hours to complete the task working alone, implies the person completes 1/9th of the job in each hour.
Let x be the hours it takes second person to complete the task working alone, implies that the person takes 1/x of the job each hour.
Working together it takes the two people to complete the job in 5 hours. That means that each hour 1/5 of the job is getting done.
Therefore 1/9 + 1/x = 1/5
subtracting 1/9 both sides we have
1/9 + 1/x - 1/9= 1/5 - 1/9
1/x = 9/45 - 5/45
1/x = 4/45
x = 45/4 or 11 1/4
The second person takes 11 1/4 hour to finish the working alone.
Directions: Solve the following word problems and show your work. Also write at least 5 word problems of your own.