TIME AND WORK FORMULAS- 1. Work from Days: If A can do a piece of work in n days, then A's 1 day's work = | 1 | . | | n | | 2. Days from Work: If A's 1 day's work = | 1 | , | then A can finish the work in n days. | | n | | | 3. Ratio:
If A is thrice as good a workman as B, then:
Ratio of work done by A and B = 3 : 1.
Ratio of times taken by A and B to finish a work = 1 : 3.

TIME AND WORK PROBLEMS- 1. | A can do a work in 15 days and B in 20 days. If they work on it together for 4 days, then the fraction of the work that is left is : | | A. | 1 | 4 | | B. | 1 | 10 | | C. | 7 | 15 | | D. | 8 | 15 | |
Answer & ExplanationAnswer: Option DExplanation: A's 1 day's work = | 1 | ; | | 15 | | B's 1 day's work = | 1 | ; | | 20 | | (A + B)'s 1 day's work = | | 1 | + | 1 | | = | 7 | . | | | 15 | | 20 | | | 60 | | (A + B)'s 4 day's work = | | 7 | x 4 | | = | 7 | . | | | 60 | | | | 15 | | Therefore, Remaining work = | | 1 - | 7 | | = | 8 | . | | | | 15 | | | 15 | |
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2. | A can lay railway track between two given stations in 16 days and B can do the same job in 12 days. With help of C, they did the job in 4 days only. Then, C alone can do the job in: | | A. | 9 | 1 | days | | 5 | | | B. | 9 | 2 | days | | 5 | | | C. | 9 | 3 | days | | 5 | | | D. | 10 |
Answer & ExplanationAnswer: Option CExplanation: (A + B + C)'s 1 day's work = | 1 | , | | 4 | | A's 1 day's work = | 1 | , | | 16 | | B's 1 day's work = | 1 | . | | 12 | | C's 1 day's work = | 1 | - | | 1 | + | 1 | | = | | 1 | - | 7 | | = | 5 | . | | 4 | | | 16 | | 12 | | | | 4 | | 48 | | | 48 | | So, C alone can do the work in | 48 | = 9 | 3 | days. | | 5 | | 5 | |
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3. | A, B and C can do a piece of work in 20, 30 and 60 days respectively. In how many days can A do the work if he is assisted by B and C on every third day? | | A. | 12 days | B. | 15 days | C. | 16 days | D. | 18 days |
Answer & ExplanationAnswer: Option BExplanation: A's 2 day's work = | | 1 | x 2 | | = | 1 | . | | | 20 | | | | 10 | | (A + B + C)'s 1 day's work = | | 1 | + | 1 | + | 1 | | = | 6 | = | 1 | . | | | 20 | | 30 | | 60 | | | 60 | | 10 | | Work done in 3 days = | | 1 | + | 1 | | = | 1 | . | | | 10 | | 10 | | | 5 | | Now, | 1 | work is done in 3 days. | | 5 | | Whole work will be done in (3 x 5) = 15 days.View Answer Workspace Report Discuss in Forum |

4. | A is thrice as good as workman as B and therefore is able to finish a job in 60 days less than B. Working together, they can do it in: | | A. | 20 days | B. | 22 | 1 | days | | 2 | | | C. | 25 days | D. | 30 days |
Answer & ExplanationAnswer: Option BExplanation:Ratio of times taken by A and B = 1 : 3.The time difference is (3 - 1) 2 days while B take 3 days and A takes 1 day.If difference of time is 2 days, B takes 3 days. If difference of time is 60 days, B takes | | 3 | x 60 | | = 90 days. | | | 2 | | | |
So, A takes 30 days to do the work. A's 1 day's work = | 1 | | 30 | B's 1 day's work = | 1 | | 90 | (A + B)'s 1 day's work = | | 1 | + | 1 | | = | 4 | = | 2 | | | 30 | | 90 | | | 90 | | 45 | A and B together can do the work in | 45 | = 22 | 1 | days. | | 2 | | 2 | |
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5. | A alone can do a piece of work in 6 days and B alone in 8 days. A and B undertook to do it for Rs. 3200. With the help of C, they completed the work in 3 days. How much is to be paid to C? | | A. | Rs. 375 | B. | Rs. 400 | C. | Rs. 600 | D. | Rs. 800 |
Answer & ExplanationAnswer: Option BExplanation: C's 1 day's work = | 1 | - | | 1 | + | 1 | | = | 1 | - | 7 | = | 1 | . | | 3 | | | 6 | | 8 | | | 3 | | 24 | | 24 | | A's wages : B's wages : C's wages = | 1 | : | 1 | : | 1 | = 4 : 3 : 1. | | 6 | | 8 | | 24 | | C's share (for 3 days) = Rs. | | 3 x | 1 | x 3200 | | = Rs. 400. | | | | 24 | | | |
View Answer Workspace Report Discuss in Forum | 6. | If 6 men and 8 boys can do a piece of work in 10 days while 26 men and 48 boys can do the same in 2 days, the time taken by 15 men and 20 boys in doing the same type of work will be: | | A. | 4 days | B. | 5 days | C. | 6 days | D. | 7 days |
Answer & ExplanationAnswer: Option AExplanation:Let 1 man's 1 day's work = x and 1 boy's 1 day's work = y. Then, 6x + 8y = | 1 | and 26x + 48y = | 1 | . | | 10 | | 2 | | Solving these two equations, we get : x = | 1 | and y = | 1 | . | | 100 | | 200 | | (15 men + 20 boy)'s 1 day's work = | | 15 | + | 20 | | = | 1 | . | | | 100 | | 200 | | | 4 | | 15 men and 20 boys can do the work in 4 days.View Answer Workspace Report Discuss in Forum |

7. | A can do a piece of work in 4 hours; B and C together can do it in 3 hours, while A and C together can do it in 2 hours. How long will B alone take to do it? | | A. | 8 hours | B. | 10 hours | C. | 12 hours | D. | 24 hours |
Answer & ExplanationAnswer: Option CExplanation: A's 1 hour's work = | 1 | ; | | 4 | | (B + C)'s 1 hour's work = | 1 | ; | | 3 | | (A + C)'s 1 hour's work = | 1 | . | | 2 | | (A + B + C)'s 1 hour's work = | | 1 | + | 1 | | = | 7 | . | | | 4 | | 3 | | | 12 | | B's 1 hour's work = | | 7 | - | 1 | | = | 1 | . | | | 12 | | 2 | | | 12 | | B alone will take 12 hours to do the work.View Answer Workspace Report Discuss in Forum |

8. | A can do a certain work in the same time in which B and C together can do it. If A and B together could do it in 10 days and C alone in 50 days, then B alone could do it in: | | A. | 15 days | B. | 20 days | C. | 25 days | D. | 30 days |
Answer & ExplanationAnswer: Option CExplanation: (A + B)'s 1 day's work = | 1 | | 10 | C's 1 day's work = | 1 | | 50 | (A + B + C)'s 1 day's work = | | 1 | + | 1 | | = | 6 | = | 3 | . .... (i) | | | 10 | | 50 | | | 50 | | 25 | |
A's 1 day's work = (B + C)'s 1 day's work .... (ii) From (i) and (ii), we get: 2 x (A's 1 day's work) = | 3 | | 25 | A's 1 day's work = | 3 | . | | 50 | | B's 1 day's work | | 1 | - | 3 | | = | 2 | = | 1 | . | | | 10 | | 50 | | | 50 | | 25 | |
So, B alone could do the work in 25 days.View Answer Workspace Report Discuss in Forum |

9. | A does 80% of a work in 20 days. He then calls in B and they together finish the remaining work in 3 days. How long B alone would take to do the whole work? | | A. | 23 days | B. | 37 days | C. | 37 | D. | 40 days |
Answer & ExplanationAnswer: Option CExplanation: Whole work is done by A in | | 20 x | 5 | | = 25 days. | | | | 4 | | | Now, | | 1 - | 4 | | i.e., | 1 | work is done by A and B in 3 days. | | | | 5 | | | 5 | |
Whole work will be done by A and B in (3 x 5) = 15 days. A's 1 day's work = | 1 | , (A + B)'s 1 day's work = | 1 | . | | 25 | | 15 | | | | | | | B's 1 day's work = | | 1 | - | 1 | | = | 4 | = | 2 | . | | | 15 | | 25 | | | 150 | | 75 | | So, B alone would do the work in | 75 | = 37 | 1 | days. | | 2 | | 2 | |
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10. | A machine P can print one lakh books in 8 hours, machine Q can print the same number of books in 10 hours while machine R can print them in 12 hours. All the machines are started at 9 A.M. while machine P is closed at 11 A.M. and the remaining two machines complete work. Approximately at what time will the work (to print one lakh books) be finished ? | | A. | 11:30 A.M. | B. | 12 noon | C. | 12:30 P.M. | D. | 1:00 P.M. |
Answer & ExplanationAnswer: Option DExplanation: (P + Q + R)'s 1 hour's work = | | 1 | + | 1 | + | 1 | | = | 37 | . | | | 8 | | 10 | | 12 | | | 120 | | Work done by P, Q and R in 2 hours = | | 37 | x 2 | | = | 37 | . | | | 120 | | | | 60 | | Remaining work = | | 1 - | 37 | | = | 23 | . | | | | 60 | | | 60 | | (Q + R)'s 1 hour's work = | | 1 | + | 1 | | = | 11 | . | | | 10 | | 12 | | | 60 | | Now, | 11 | work is done by Q and R in 1 hour. | | 60 | | So, | 23 | work will be done by Q and R in | | 60 | x | 23 | | = | 23 | hours 2 hours. | | 60 | | | 11 | | 60 | | | 11 | |
So, the work will be finished approximately 2 hours after 11 A.M., i.e., around 1 P.M.View Answer Workspace Report Discuss in Forum | 11. | A can finish a work in 18 days and B can do the same work in 15 days. B worked for 10 days and left the job. In how many days, A alone can finish the remaining work? | | A. | 5 | B. | 5 | 1 | | 2 | | C. | 6 | D. | 8 |
Answer & ExplanationAnswer: Option CExplanation: B's 10 day's work = | | 1 | x 10 | | = | 2 | . | | | 15 | | | | 3 | | Remaining work = | | 1 - | 2 | | = | 1 | . | | | | 3 | | | 3 | | Now, | 1 | work is done by A in 1 day. | | 18 | | | 1 | work is done by A in | | 18 x | 1 | | = 6 days. | | 3 | | | | 3 | | |
View Answer Workspace Report Discuss in Forum | 12. | 4 men and 6 women can complete a work in 8 days, while 3 men and 7 women can complete it in 10 days. In how many days will 10 women complete it? | | A. | 35 | B. | 40 | C. | 45 | D. | 50 |
Answer & ExplanationAnswer: Option BExplanation:Let 1 man's 1 day's work = x and 1 woman's 1 day's work = y. Then, 4x + 6y = | 1 | and 3x + 7y = | 1 | . | | 8 | | 10 | | Solving the two equations, we get: x = | 11 | , y = | 1 | | 400 | | 400 | 1 woman's 1 day's work = | 1 | . | | 400 | | 10 women's 1 day's work = | | 1 | x 10 | | = | 1 | . | | | 400 | | | | 40 | |
Hence, 10 women will complete the work in 40 days.View Answer Workspace Report Discuss in Forum | 13. | A and B can together finish a work 30 days. They worked together for 20 days and then B left. After another 20 days, A finished the remaining work. In how many days A alone can finish the work? | | A. | 40 | B. | 50 | C. | 54 | D. | 60 |
Answer & ExplanationAnswer: Option DExplanation: (A + B)'s 20 day's work = | | 1 | x 20 | | = | 2 | . | | | 30 | | | | 3 | | Remaining work = | | 1 - | 2 | | = | 1 | . | | | | 3 | | | 3 | | Now, | 1 | work is done by A in 20 days. | | 3 | |
Therefore, the whole work will be done by A in (20 x 3) = 60 days.View Answer Workspace Report Discuss in Forum | 14. | P can complete a work in 12 days working 8 hours a day. Q can complete the same work in 8 days working 10 hours a day. If both P and Q work together, working 8 hours a day, in how many days can they complete the work? | | A. | 5 | 5 | | 11 | | B. | 5 | 6 | | 11 | | C. | 6 | 5 | | 11 | | D. | 6 | 6 | | 11 | |
Answer & ExplanationAnswer: Option AExplanation:P can complete the work in (12 x 8) hrs. = 96 hrs.Q can complete the work in (8 x 10) hrs. = 80 hrs. P's1 hour's work = | 1 | and Q's 1 hour's work = | 1 | . | | 96 | | 80 | | (P + Q)'s 1 hour's work = | | 1 | + | 1 | | = | 11 | . | | | 96 | | 80 | | | 480 | | So, both P and Q will finish the work in | | 480 | | hrs. | | | 11 | | | Number of days of 8 hours each = | | 480 | x | 1 | | = | 60 | days = 5 | 5 | days. | | | 11 | | 8 | | | 11 | | 11 | |
View Answer Workspace Report Discuss in Forum | 15. | 10 women can complete a work in 7 days and 10 children take 14 days to complete the work. How many days will 5 women and 10 children take to complete the work? | | A. | 3 | B. | 5 | C. | 7 | D. | Cannot be determined | E. | None of these | | |
Answer & ExplanationAnswer: Option CExplanation: 1 woman's 1 day's work = | 1 | | 70 | 1 child's 1 day's work = | 1 | | 140 | (5 women + 10 children)'s day's work = | | 5 | + | 10 | | = | | 1 | + | 1 | | = | 1 | | | 70 | | 140 | | | | 14 | | 14 | | | 7 | 5 women and 10 children will complete the work in 7 days.View Answer Workspace Report Discuss in Forum | | 16. | X and Y can do a piece of work in 20 days and 12 days respectively. X started the work alone and then after 4 days Y joined him till the completion of the work. How long did the work last? | | A. | 6 days | B. | 10 days | C. | 15 days | D. | 20 days |
Answer & ExplanationAnswer: Option BExplanation: Work done by X in 4 days = | | 1 | x 4 | | = | 1 | . | | | 20 | | | | 5 | | Remaining work = | | 1 - | 1 | | = | 4 | . | | | | 5 | | | 5 | | (X + Y)'s 1 day's work = | | 1 | + | 1 | | = | 8 | = | 2 | . | | | 20 | | 12 | | | 60 | | 15 | | Now, | 2 | work is done by X and Y in 1 day. | | 15 | | So, | 4 | work will be done by X and Y in | | 15 | x | 4 | | = 6 days. | | 5 | | | 2 | | 5 | | |
Hence, total time taken = (6 + 4) days = 10 days.View Answer Workspace Report Discuss in Forum |

17. | A is 30% more efficient than B. How much time will they, working together, take to complete a job which A alone could have done in 23 days? | | A. | 11 days | B. | 13 days | C. | 20 | 3 | days | | 17 | | | D. | None of these |
Answer & ExplanationAnswer: Option BExplanation:Ratio of times taken by A and B = 100 : 130 = 10 : 13.Suppose B takes x days to do the work. Then, 10 : 13 :: 23 : x x = | | 23 x 13 | | x = | 299 | . | | | 10 | | | 10 | | A's 1 day's work = | 1 | ; | | 23 | | B's 1 day's work = | 10 | . | | 299 | | (A + B)'s 1 day's work = | | 1 | + | 10 | | = | 23 | = | 1 | . | | | 23 | | 299 | | | 299 | | 13 | |
Therefore, A and B together can complete the work in 13 days.View Answer Workspace Report Discuss in Forum |

18. | Ravi and Kumar are working on an assignment. Ravi takes 6 hours to type 32 pages on a computer, while Kumar takes 5 hours to type 40 pages. How much time will they take, working together on two different computers to type an assignment of 110 pages? | | A. | 7 hours 30 minutes | B. | 8 hours | C. | 8 hours 15 minutes | D. | 8 hours 25 minutes |
Answer & ExplanationAnswer: Option CExplanation: Number of pages typed by Ravi in 1 hour = | 32 | = | 16 | . | | 6 | | 3 | | Number of pages typed by Kumar in 1 hour = | 40 | = 8. | | 5 | | Number of pages typed by both in 1 hour = | | 16 | + 8 | | = | 40 | . | | | 3 | | | | 3 | | Time taken by both to type 110 pages = | | 110 x | 3 | | hours | | | | 40 | | | = 8 | 1 | hours (or) 8 hours 15 minutes. | | 4 | |
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19. | A, B and C can complete a piece of work in 24, 6 and 12 days respectively. Working together, they will complete the same work in: | | A. | 1 | day | 24 | | | B. | 7 | day | 24 | | | C. | 3 | 3 | days | | 7 | | | D. | 4 days |
Answer & ExplanationAnswer: Option CExplanation: Formula: If A can do a piece of work in n days, then A's 1 day's work = | 1 | . | | n | | (A + B + C)'s 1 day's work = | | 1 | + | 1 | + | 1 | | = | 7 | . | | | 24 | | 6 | | 12 | | | 24 | | Formula: If A's 1 day's work = | 1 | , | then A can finish the work in n days. | | n | | | So, all the three together will complete the job in | | 24 | days | = | 3 | 3 | days. | | | 7 | | | | 7 | |
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20. | Sakshi can do a piece of work in 20 days. Tanya is 25% more efficient than Sakshi. The number of days taken by Tanya to do the same piece of work is: | | A. | 15 | B. | 16 | C. | 18 | D. | 25 |
Answer & ExplanationAnswer: Option BExplanation:Ratio of times taken by Sakshi and Tanya = 125 : 100 = 5 : 4.Suppose Tanya takes x days to do the work. 5 : 4 :: 20 : x x = | | 4 x 20 | | | | 5 | | x = 16 days.Hence, Tanya takes 16 days to complete the work.View Answer Workspace Report Discuss in Forum | 21. | A takes twice as much time as B or thrice as much time as C to finish a piece of work. Working together, they can finish the work in 2 days. B can do the work alone in: | | A. | 4 days | B. | 6 days | C. | 8 days | D. | 12 days |
Answer & ExplanationAnswer: Option BExplanation: Suppose A, B and C take x, | x | and | x | days respectively to finish the work. | | 2 | | 3 | | Then, | | 1 | + | 2 | + | 3 | | = | 1 | | | x | | x | | x | | | 2 | | 6 | = | 1 | | x | | 2 | x = 12.So, B takes (12/2) = 6 days to finish the work.View Answer Workspace Report Discuss in Forum |

22. | A and B can complete a work in 15 days and 10 days respectively. They started doing the work together but after 2 days B had to leave and A alone completed the remaining work. The whole work was completed in : | | A. | 8 days | B. | 10 days | C. | 12 days | D. | 15 days |
Answer & ExplanationAnswer: Option CExplanation: (A + B)'s 1 day's work = | | 1 | + | 1 | | = | 1 | . | | | 15 | | 10 | | | 6 | | Work done by A and B in 2 days = | | 1 | x 2 | | = | 1 | . | | | 6 | | | | 3 | | Remaining work = | | 1 - | 1 | | = | 2 | . | | | | 3 | | | 3 | | Now, | 1 | work is done by A in 1 day. | | 15 | | | 2 | work will be done by a in | | 15 x | 2 | | = 10 days. | | 3 | | | | 3 | | |
Hence, the total time taken = (10 + 2) = 12 days.View Answer Workspace Report Discuss in Forum |

23. | A and B can do a piece of work in 30 days, while B and C can do the same work in 24 days and C and A in 20 days. They all work together for 10 days when B and C leave. How many days more will A take to finish the work? | | A. | 18 days | B. | 24 days | C. | 30 days | D. | 36 days |
Answer & ExplanationAnswer: Option AExplanation: 2(A + B + C)'s 1 day's work = | | 1 | + | 1 | + | 1 | | = | 15 | = | 1 | . | | | 30 | | 24 | | 20 | | | 120 | | 8 | | Therefore, (A + B + C)'s 1 day's work = | 1 | = | 1 | . | | 2 x 8 | | 16 | | Work done by A, B, C in 10 days = | 10 | = | 5 | . | | 16 | | 8 | | Remaining work = | | 1 - | 5 | | = | 3 | . | | | | 8 | | | 8 | | A's 1 day's work = | | 1 | - | 1 | | = | 1 | . | | | 16 | | 24 | | | 48 | | Now, | 1 | work is done by A in 1 day. | | 48 | | So, | 3 | work will be done by A in | | 48 x | 3 | | = 18 days. | | 8 | | | | 8 | | |
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24. | A works twice as fast as B. If B can complete a work in 12 days independently, the number of days in which A and B can together finish the work in : | | A. | 4 days | B. | 6 days | C. | 8 days | D. | 18 days |
Answer & ExplanationAnswer: Option AExplanation:Ratio of rates of working of A and B = 2 : 1.So, ratio of times taken = 1 : 2. B's 1 day's work = | 1 | . | | 12 | | A's 1 day's work = | 1 | ; (2 times of B's work) | | 6 | | (A + B)'s 1 day's work = | | 1 | + | 1 | | = | 3 | = | 1 | . | | | 6 | | 12 | | | 12 | | 4 | |
So, A and B together can finish the work in 4 days.View Answer Workspace Report Discuss in Forum |

25. | Twenty women can do a work in sixteen days. Sixteen men can complete the same work in fifteen days. What is the ratio between the capacity of a man and a woman? | | A. | 3 : 4 | B. | 4 : 3 | C. | 5 : 3 | D. | Data inadequate |
Answer & ExplanationAnswer: Option BExplanation:(20 x 16) women can complete the work in 1 day. 1 woman's 1 day's work = | 1 | . | | 320 | |
(16 x 15) men can complete the work in 1 day. 1 man's 1 day's work = | 1 | | 240 | So, required ratio | = | 1 | : | 1 | | 240 | | 320 | | | = | 1 | : | 1 | | 3 | | 4 | | | = 4 : 3 (cross multiplied) |
View Answer Workspace Report Discuss in Forum | 26. | A and B can do a work in 8 days, B and C can do the same work in 12 days. A, B and C together can finish it in 6 days. A and C together will do it in : | | A. | 4 days | B. | 6 days | C. | 8 days | D. | 12 days |
Answer & ExplanationAnswer: Option CExplanation: (A + B + C)'s 1 day's work = | 1 | ; | | 6 | | (A + B)'s 1 day's work = | 1 | ; | | 8 | | (B + C)'s 1 day's work = | 1 | . | | 12 | | (A + C)'s 1 day's work | = | | 2 x | 1 | | - | | 1 | + | 1 | | | | | 6 | | | | 8 | | 12 | | | | = | | 1 | - | 5 | | | | 3 | | 24 | | | | = | 3 | | 24 | | | = | 1 | . | | 8 | | |
So, A and C together will do the work in 8 days.View Answer Workspace Report Discuss in Forum |

27. | A can finish a work in 24 days, B in 9 days and C in 12 days. B and C start the work but are forced to leave after 3 days. The remaining work was done by A in: | | A. | 5 days | B. | 6 days | C. | 10 days | D. | 10 | 1 | days | | 2 | | |
Answer & ExplanationAnswer: Option CExplanation: (B + C)'s 1 day's work = | | 1 | + | 1 | | = | 7 | . | | | 9 | | 12 | | | 36 | | Work done by B and C in 3 days = | | 7 | x 3 | | = | 7 | . | | | 36 | | | | 12 | | Remaining work = | | 1 - | 7 | | = | 5 | . | | | | 12 | | | 12 | | Now, | 1 | work is done by A in 1 day. | | 24 | | So, | 5 | work is done by A in | | 24 x | 5 | | = 10 days. | | 12 | | | | 12 | | |
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28. | X can do a piece of work in 40 days. He works at it for 8 days and then Y finished it in 16 days. How long will they together take to complete the work? | | A. | 13 | 1 | days | | 3 | | | B. | 15 days | C. | 20 days | D. | 26 days |
Answer & ExplanationAnswer: Option AExplanation: Work done by X in 8 days = | | 1 | x 8 | | = | 1 | . | | | 40 | | | | 5 | | Remaining work = | | 1 - | 1 | | = | 4 | . | | | | 5 | | | 5 | | Now, | 4 | work is done by Y in 16 days. | | 5 | | Whole work will be done by Y in | | 16 x | 5 | | = 20 days. | | | | 4 | | | X's 1 day's work = | 1 | , Y's 1 day's work = | 1 | . | | 40 | | 20 | | (X + Y)'s 1 day's work = | | 1 | + | 1 | | = | 3 | . | | | 40 | | 20 | | | 40 | | Hence, X and Y will together complete the work in | | 40 | | = 13 | 1 | days. | | | 3 | | | 3 | |
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29. | A and B can do a job together in 7 days. A is 1 times as efficient as B. The same job can be done by A alone in : | | A. | 9 | 1 | days | | 3 | | | B. | 11 days | C. | 12 | 1 | days | | 4 | | | D. | 16 | 1 | days | | 3 | | |
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30. | A and B together can do a piece of work in 30 days. A having worked for 16 days, B finishes the remaining work alone in 44 days. In how many days shall B finish the whole work alone? | | A. | 30 days | B. | 40 days | C. | 60 days | D. | 70 days |
Answer & ExplanationAnswer: Option CExplanation:Let A's 1 day's work = x and B's 1 day's work = y. Then, x + y = | 1 | and 16x + 44y = 1. | | 30 | | Solving these two equations, we get: x = | 1 | and y = | 1 | | 60 | | 60 | B's 1 day's work = | 1 | . | | 60 | |
Hence, B alone shall finish the whole work in 60 days.View Answer Workspace Report Discuss in Forum |