Subject Category > Mathematics

Q. A and B can together do a work in 6 days. A can do it alone in 9 days. In how many days can B do it alone?

A) 21 days

B) 24 days

C) 18 days

D) 14 days

✔ 18 days

Additional Information > Exam point of View

The work rate of A and B together is 1/6, and A's rate is 1/9. B's rate is (1/6 - 1/9) = 1/18. Therefore, B can complete the work alone in 18 days.

Asked Question

Q 1.The average marks obtained by 120 students in an exam is 35. If the average marks obtained by successful students is 39 and the average marks obtained by unsuccessful students is 15 then what is the number of successful students?

Right Answer : 100

View Explanation
Q 2.A train travels from A to B at the speed of 20 km./hr. and from B to A at the speed of 30 km./hr. Then what is the average speed of train in km./hr.?

Right Answer : 24 km./hr

View Explanation
Q 3.There is a loss of 12 percent on an article being sold for Rs. 352.88, then the cost price of the article is

Right Answer : Rs. 401

View Explanation
Q 4.After 5 years, fathers’ age will be three times the age of son. Five years earlier father’s age was 7 times the age of son at that time. What are the present ages of the father and the son?

Right Answer : 40 years, 10 years

View Explanation
Q 5.Rs. 7500 has been borrowed at 4% annual compound rate of interest. How much money will have to be returned after two years?

Right Answer : Rs. 8112

View Explanation
Q 6.A can do a work in 6 days and B can do it in 5 days. The contract for the work is Rs. 220. If A and B work together then how much money should B get?

Right Answer : Rs. 120

View Explanation
Q 7.In a hundred metres race, A defeats B by 10 metres and C by 13 metres, then in the 10 metres race by what distance will B defeat C?

Right Answer : 6 metres

View Explanation
Q 8.When two pipes work together, then a tank can be filled in 12 hours. One pipe fills the tank comparatively 10 hours faster than the other pipe. How much time will the pipe which is faster take to fill the tank?

Right Answer : 20 hrs.

View Explanation
Q 9.A boy goes from home to school at the rate of 3 km./hr. and come back from school to home at the speed of 2 km./hr. If he takes five hours in coming and going, then what is the distance between home and school?

Right Answer : 6 km

View Explanation
Q 10.A man rows a boat at the speed of 6 km./hr. in still water. When the river flows with the speed 1.2 km./hr, then it takes 1 hour for the man to row from one place to another. How far is that place?

Right Answer : 2.88 km

View Explanation

Find Teachers, Institutes & Coaching Centers Profiles, Articles, & Test Series