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Time and Work Questions Answers

  • 1. Worker A takes 8 hours to do a job. Worker B takes 10 hours to do a job. How long should it take both A and B, working together to do same job.

    1. \begin{aligned} \frac{4}{9} \end{aligned}
    2. \begin{aligned} 2\frac{4}{9} \end{aligned}
    3. \begin{aligned} 3\frac{4}{9} \end{aligned}
    4. \begin{aligned} 4\frac{4}{9} \end{aligned}
    Answer And Explanation

    Answer: Option D

    Explanation:

    In this type of questions, first we need to calculate 1 hours work, then their collective work as,

    A's 1 hour work is 1/8
    B's 1 hour work is 1/10

    (A+B)'s 1 hour work = 1/8 + 1/10
    = 9/40

    So both will finish the work in 40/9 hours
    = \begin{aligned} 4\frac{4}{9} \end{aligned}

  • 2. A and B can together complete a piece of work in 4 days. If A alone can complete the same work in 12 days, in how many days can B alone complete that work ?

    1. 4 days
    2. 5 days
    3. 6 days
    4. 7 days
    Answer And Explanation

    Answer: Option C

    Explanation:

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

    A's 1 day work = 1/12

    B's 1 day work =
    \begin{aligned}
    \left( \frac{1}{4} - \frac{1}{12} \right) \\
    = \frac{3-1}{12} \\
    = \frac{1}{6} \\
    \end{aligned}

    So B alone can complete the work in 6 days

  • 3. A does a work in 10 days and B does the same work in 15 days. In how many days they together will do the same work ?

    1. 5 days
    2. 6 days
    3. 7 days
    4. 8 days
    Answer And Explanation

    Answer: Option B

    Explanation:

    Firstly we will find 1 day work of both A and B, then by adding we can get collective days for them,
    So,
    A's 1 day work = 1/10
    B's 1 day work = 1/15

    (A+B)'s 1 day work =
    \begin{aligned}
    \left(\frac{1}{10}+\frac{1}{15} \right) \\
    =\left(\frac{3+2}{30} \right) \\
    = \frac{1}{6}
    \end{aligned}

    So together they can complete work in 6 days.

  • 4. A can finish a work in 18 days and B can do same work in half the time taken by A. then working together, what part of same work they can finish in a day

    1. 1\5
    2. 1\6
    3. 1\7
    4. 1\8
    Answer And Explanation

    Answer: Option B

    Explanation:

    Please note in this question, we need to answer part of work for a day rather than complete work. It was worth mentioning here because many do mistake at this point in hurry to solve the question

    So lets solve now,
    A's 1 day work = 1/18
    B's 1 day work = 1/9 [because B take half time than A]

    (A+B)'s one day work =

    \begin{aligned}
    \left(\frac{1}{18}+\frac{1}{9} \right) \\
    =\left(\frac{1+2}{18} \right) \\
    = \frac{1}{6}
    \end{aligned}

    So in one day 1/6 work will be done.

  • 5. A tyre has two punctures. The first puncture alone would have made the tyre flat in 9 minutes and the second alone would have done it in 6 minutes. If air leaks out at a constant rate, how long does it take both the punctures together to make it flat ?

    1. \begin{aligned} 3\frac{1}{5} min \end{aligned}
    2. \begin{aligned} 3\frac{2}{5} min \end{aligned}
    3. \begin{aligned} 3\frac{3}{5} min \end{aligned}
    4. \begin{aligned} 3\frac{4}{5} min \end{aligned}
    Answer And Explanation

    Answer: Option C

    Explanation:

    Do not be confused, Take this question same as that of work done question's. Like work done by 1st puncture in 1 minute and by second in 1 minute.
    Lets Solve it:

    1 minute work done by both the punctures =
    \begin{aligned}
    \left(\frac{1}{9}+\frac{1}{6} \right) \\
    =\left(\frac{5}{18} \right) \\
    \end{aligned}

    So both punctures will make the type flat in
    \begin{aligned}
    \left(\frac{18}{5} \right)mins \\
    = 3\frac{3}{5} mins
    \end{aligned}

  • 6. A is twice as good as workman as B and together they finish a piece of work in 18 days. In how many days will B alone finish the work.

    1. 27 days
    2. 54 days
    3. 56 days
    4. 68 days
    Answer And Explanation

    Answer: Option B

    Explanation:

    As per question, A do twice the work as done by B.
    So A:B = 2:1
    Also (A+B) one day work = 1/18

    To get days in which B will finish the work, lets calculate work done by B in 1 day =
    \begin{aligned}
    =\left(\frac{1}{18}*\frac{1}{3} \right) \\
    = \frac{1}{54}
    \end{aligned}
    [Please note we multiplied by 1/3 as per B share and total of ratio is 1/3]

    So B will finish the work in 54 days

  • 7. A man can do a piece of work in 5 days, but with the help of his son he can do it in 3 days. In what time can the son do it alone ?

    1. \begin{aligned} 7\frac{1}{2}days \end{aligned}
    2. \begin{aligned} 6\frac{1}{2}days \end{aligned}
    3. \begin{aligned} 5\frac{1}{2}days \end{aligned}
    4. \begin{aligned} 4\frac{1}{2}days \end{aligned}
    Answer And Explanation

    Answer: Option A

    Explanation:

    In this type of question, where we have one person work and together work done. Then we can easily get the other person work just by subtracting them. As,

    Son's one day work =
    \begin{aligned}
    \left(\frac{1}{3}-\frac{1}{5} \right) \\
    =\left(\frac{5-3}{15} \right) \\
    = \frac{2}{15}
    \end{aligned}

    So son will do whole work in 15/2 days
    which is =

    \begin{aligned} 7\frac{1}{2}days \end{aligned}

Post a comment

  • Bivash Biswas 7 years ago

    A+B in 8 day = 1/12 *8=2/3
    so, reaming work is 1- 2/3=1/3 which is done by B in 10 days so B will do the whole work in 3*10=30 days
    so A alone can do this in 1/12-1/30=1/20=20 days

  • Nithil N R Irinjalakuda 7 years ago

    A is twice as efficient as B .B started the work and after 4 days A joins B and total work was completed in 9 days.in how many days B can complete the work alone ?
    Give me solution

  • Rekha Suresh 7 years ago

    A can do piece of work in 30days.he works at it for 5days and then B finishs itin 20 days.In what time A and B together can finish it?

    a.16 2/3 b.13 1/3 c.17 1/3 d.16 1/2

  • mini 8 years ago

    A and B can do a piece of work in 18 and 24 days respectively. they together can do in 8 days and then A left. the remaining work was finished by B in how many days please answer the question

  • mahi 8 years ago

    : A and B
    together can complete a work in 3 day. they start together. but after 2 days, B
    left the work. if the work is completed after 2 more days, B alone could do the
    work in how many days?

  • PRACHI 8 years ago

    45 MEN can do a work in 16 days. 6 days after starting work 30 more men joined the work. In how many days will the remaining work be completed?

    plz answer

  • Sudipto Sarkar 8 years ago

    like..

  • Ranjeet Singh 8 years ago

    A and B can do a piece of work in 30 days B and C together can do it in
    20 days.A starts work and works on it for 5 days, then B takes up and
    works for 15 days finally C finishes work in 18 days. the number of days
    in which C alone can do a work when doing it seperately?

  • prasana 8 years ago

    A and B ONE DAY WORK IS 1/12
    A and B 8 DAY WORK IS 8/12=2/3 REMAINING WORK IS 1/3
    B ALONE CAN DO 1/3 OF WORK IN ONE DAY . IN 10 DAYS IT TAKES 10/3DAYS

  • Charu 8 years ago

    If 3 men or 4 women can do a work in 43 days how long will 7 men and 5 women take to complete the work?

    Can you please solve this question, and explain the answer as well??

    Thanks!

    Saurabh Kumar 8 years ago replied

    (3*4*43)/(3*5+7*4)=12 DAYS

    Saurabh Kumar 8 years ago replied

    efficiency of (A=6,B=3,C=2)
    B WORK ALONE=(3*2)=6DAYS

    Ranjeet Singh 8 years ago replied

    solve friends.....how can we calculate one day work of a singe person in this?

  • Sarbeswar Panda 8 years ago

    A takes three times as long as B & C.B takes four times as long as A & C together to do this work.If all three ,working together can complete the job in 24 Days,then the no of days A alone can do this job is

  • Abhinandan 8 years ago

    I am agree with adarsha
    So answer is 20 days

  • Abhinandan 8 years ago

    384 rupees

    divya 8 years ago replied

    give explaination pls

  • FLDSMFR 8 years ago

    Put your di.ck in my vagi.na

  • IMe Myself 8 years ago

    Yeah. He Sucks A ****.

  • IMe Myself 8 years ago

    Yoyo Honey Singh

  • teja 9 years ago

    100 workers should share 100 rupees.Each Man gets 4 rupees, each woman gets 0.50 rupees, each child gets 0.25 rupees. how many men,women,children are there?

  • lavanya 9 years ago

    A can finish 1/5th of his work in 1hr,B can finish 3/7th of his work in 1hr 30 mins and C can finish his 3/4th of his work in 3hr 30 mins. if they all start their work at 12pm,and gog to play as soon as they finish their work. when can they start their play when they take a break at 3.30pm for 30 mins

    bhavesh 8 years ago replied

    they can start there play at 5:30 pm

  • Rajalakshmi Prasanna Mallampal 9 years ago

    5 people can consume 50 kg rice in 30 days. In how many days 35 people can consume 70 kg rice?

    Bibekanand Das 9 years ago replied

    30 x 35/5 x 70/50 = 294

    bhavesh 8 years ago replied

    6 days

  • Akshay Prabhu 9 years ago

    Mast guru mast site and mast questions Thnk u very much... :)

  • Harjinder 9 years ago

    ek scotar k three tyre hai ek tyre sey scoter sirf 5 km chal sakta hai then btao scotar
    total kitna km chal skta hai

  • durgesh singh 9 years ago

    A+B= 12 Days, in 8 Days work Completed = 8/12(Since both worked), so work left = 1 - (8/12) = 1/3.
    Now B takes 10 Days to complete 1/3 work, so B takes 30 days alone to complete work (10x3).

    Now, A+B = 12 days, B = 30 Days , there for A = 20 Days

  • Jyoti 9 years ago

    A contractor undertake to do a piece of work in 150 days, so he deployed 200 men. He found that only a quarter of work is done in 50 days. How many additional men must be deployed so that the work may be finished on tine.

    durgesh singh 9 years ago replied

    200menx50Days = 1/4 of work , so Total work = 200*50*4.
    Now Let extra Men reqquired is x

    Therefore , (200+x)*100(remaining Days)=3/4of work (That is remaining work).

    so , (200+x)*100 = 200*50*4*(3/4)
    => 200+x=300
    => x= 100

  • Gurpreet Singh 10 years ago

    A and B can do a job together in 7 days . A is 7/4 times as efficient as B.The same job can be done by A alone in:

    fidha 9 years ago replied

    suppose B takes x days.so A will take x/7/4.
    according to the question,1/x/7/4+1/x=1/7
    solving this one,we get like this as follows.
    11/4x=1/7
    x=77/4=19 1/4 days

    Guest 9 years ago replied

    4 days

  • aditi 10 years ago

    Plz explain 20th question

  • Yuvashree Mani 10 years ago

    A TAKES TWICE AS MUCH TIME AS B OR THRICE AS MUCH AS C TO FINISH WORK..WORKING TOGETHER THEY FINISH IN 2DAYS..IN HOW MANY DAYS CAN B DO SAME WRK??

    Akanksha Gautam 10 years ago replied

    6 days

    Ravi 9 years ago replied

    1.5 days..

    pan masala 9 years ago replied

    1/x + 2/x +3/x = 1/2

    x=12

    so B takes x/2= 6 days

  • pradeep 10 years ago

    i didnt get 6th que why multiplied by 1/3?

    mastguru 10 years ago replied

    Hello Pradeep,

    As A:B = 2:1,
    B share will be 1/(2+1) = 1/3

  • vignesh 10 years ago

    6 men and 8 women do a piece of work in 10 days and 3 men and 2 women do the same in 25 days.In how many days 5 men and 4 women can complete the same work??

  • dk 10 years ago

    not thatr greatr

  • jvshyamprasad 10 years ago

    its better sir thanks

  • M PRABHAKARREDDY 10 years ago

    good