A is 4 times as fast as B and therefore is able to finish the work in 45 days less than B. A and B, can complete the work in how many days?
Explanation
A is 4 times as fast as B, so A's rate of work is 4 times B's rate of work.
Since A finishes the work in 45 days less than B, let's assume B takes x days to finish the work. Then A takes x - 45 days to finish the work.
Since A is 4 times as fast as B, A's rate of work is 4 times B's rate of work. So, A's time to finish the work is 1/4 of B's time.
We can set up an equation based on the above: x - 45 = (1/4)x
Solve for x: x - 45 = (1/4)x --> 4x - 180 = x --> 3x = 180 --> x = 60
So B takes 60 days to finish the work, and A takes 60 - 45 = 15 days to finish the work.
Since A and B work together, their combined rate of work is the sum of their individual rates. Let's find their individual rates.
B's rate = 1/60 (work done per day)
A's rate = 1/15 (work done per day)
Combined rate = (1/60 + 1/15) = (1/60 + 4/60) = 5/60 = 1/12
So A and B together can complete the work in 12 days.
Related MCQs
- P and Q can complete a work in 15 days and 10 days respectively. They started the work together and then Q left after 2 days. P alone completed the remaining work. The work was finished in _______ days.
- P and Q need 8 days to complete a work. Q and R need 12 days to complete the same work. But P, Q and R together can finish it in 6 days. How many days will be needed if P and R together do it?
- A and B together can complete a work in 3 days. They start together but after 2 days, B left the work. If the work is completed after two more days, B alone could do the work in ____?
- Sixteen men can complete a work in twelve days. Twenty-four children can complete the same work in eighteen days. Twelve men and eight children started working and after eight days three more children joined them. How many days will they now take to complete the remaining work?
- Twenty-four men can complete a work in sixteen days. Thirty-two women can complete the same work in twenty-four days. Sixteen men and sixteen women started working and worked for twelve days. How many more men are to be added to complete the remaining work in 2 days?
- A is thrice as good as B in work. A is able to finish a job in 60 days less than B. They can finish the work in ______ days if they work together.
- A completes a work in 12 days. B completes the same work in 15 days. A started working alone and after 3 days B joined him. How many days will they now take together to complete the remaining work?
- Shaista completes a piece of work in 10 days, All completes the same work in 40 days, if they work together, the days required to complete the work will be _________
- 12 men can complete a work in 90 days. 30 days after they started work, 2 men left and 8 men joined. How many days will it take to complete the remaining work_____?
- 12 men can complete a piece of work in 4 days, while 15 women can complete the same work in 4 days. 6 men start working on the job, and after working for 2 days, all of them stopped working. How many women should be put on the job to complete the remaining work, if it is to be completed in 3 days?