43.7k views
4 votes
Please help me with this word problem quickly, work is needed thank you!

Please help me with this word problem quickly, work is needed thank you!-example-1
User Beinghuman
by
5.4k points

1 Answer

2 votes

Given:

Sheila can wash her car in 15 minutes. Bob takes time twice as long to wash the same car.

Required:

Find the time they take both together.

Step-by-step explanation:

Sheila can wash her car in 15 minutes.

Work done by sheila in a minute =


(1)/(15)\text{ }

Bob takes time twice as long to wash the same car. He washes the car in 30 minutes.

Work done by Bob in a minute


=(1)/(30)

If they work together let them take time x per minute.


(1)/(15)+(1)/(30)=(1)/(x)

Solve by taking L.C. M.


\begin{gathered} (2+1)/(30)=(1)/(x) \\ (3)/(30)=(1)/(x) \\ (1)/(10)=(1)/(x) \\ x=10\text{ minutes.} \end{gathered}

If they work together they will take 10 minutes.

Final Answer:

Sheila and Bob wash the car together in 10 minutes.

User Dan Manastireanu
by
5.0k points