English

A Can Do a Piece of Work in 10 Days; B in 18 Days; and A, B, and C Together in 4 Days. in What Time Would C Alone Do It? - Mathematics

Advertisements
Advertisements

Question

A can do a piece of work in 10 days; B in 18 days; and A, B, and C together in 4 days. In what time would C alone do it?

Sum

Solution

A can do a piece of work in = 10 days

B can do a piece of work in = 18 days

(A+B+C) can do a piece of work in = 4 days

∴ A's 1-day work =`1/10`

B's 1-day work = `1/18`

(A+B)'s 1-day work =`1/10+1/18=(9+5)/90`

`=14/90=7/45`

(A+B+C)'s 1-day work =`1/4`

∴ C's 1-day work =`1/4-7/45`

`=(45-28)/180=17/180`

∴ C can do the piece of work in = `180/17` days

`=10 10/17` days

shaalaa.com
Time and Work
  Is there an error in this question or solution?
Chapter 10: Direct and Inverse Variations - Exercise 10 (E) [Page 133]

APPEARS IN

Selina Concise Mathematics [English] Class 8 ICSE
Chapter 10 Direct and Inverse Variations
Exercise 10 (E) | Q 9 | Page 133

RELATED QUESTIONS

A train is moving with a uniform speed of 120 km per hour.
(i) How far will it travel in 36 minutes?
(ii) In how much time will it cover 210 km?


If 3 men or 6 boys can finish a work in 20 days, how long will 4 men and 12 boys take to finish the same work?


A contractor undertakes to dig a canal, 6 kilometers long, in 35 days and employed 90 men. He finds that after 20 days only 2 km of the canal has been completed. How many more men must be employed to finish the work on time?


A and B together can do a piece of work in `6 2/3` days, but B alone can do it in 10 days. How long will A take to do it alone?


A can do a work in 15 days and B in 20 days. If they together work on it for 4 days; what fraction of the work will be left?


A, B, and C can do a piece of work in 6 days, 12 days, and 24 days respectively. In what time will they altogether do it?


A can do a piece of work in 20 days and B in 15 days. They worked together on it for 6 days and then A left. How long will B take to finish the remaining work?


A can finish a piece of work in 15 days and B can do it in 10 days. They worked together for 2 days and then B goes away. In how many days will A finish the remaining work?


A and B can do a work in 8 days; B and C in 12 days, and A and C in 16 days. In what time could they do it, all working together?


P and Q can do a piece of work in 12 days and 15 days respectively. P started the work alone and then after 3 days, Q joined him till the work was completed. How long did the work last?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×