Maths Problem : Time and Work


Question : A can complete the work in 12 days and B can complete the same work in 15 days . Both started the work together but after four days A left the work . In how many says work will be completed ?

 Solution : Let work is completed in X days 

 Fraction of work done by A + Fraction of work done by B = 1

 ( 4/12) + (X/ 15) = 1
X = 10 days

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 Question : Pipe A an fill the tank in 25 hours while B alone an fill it in 30 hours and Pipe C can empty the tank in 20 Hours . If all the pipe  is open together , after how much time tank will be full ?
maths problem time and work

 Solution :   In one Hour Fraction by which tank will be filled = (1/25)+(1/30)-(1/20)

                                                                                        = (350 / 15000)

                            Tank will be full in = 15000 / 350 = 42.85 Hours
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Question : A and B can finish the work in 10 days while B and C can do  it in 18 days . A started the work and left after 5 days then be worked for 10 days and left . If C completed the remaining work in 15 days then how many days could C alone have finished the whole work ?

Answer : 45 days

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Question : A certain number of worker are required to complete the work in 24 days . The work however took 32 days  as 9 worker were absent all the time . How many worker were working originally ?


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Label : Maths for Kids , Maths Puzzle , Brain Tester ,  Maths Question , Time and work, Maths Problems , Maths worksheet , LCM HCF , Algebra, Bank PO exam, SSC Exam

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