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A, B and C can do a work in 6, 8, 12 days respectively. B and C work t
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30 Jan 2019, 02:19
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42% (01:43) correct 58% (01:49) wrong based on 81 sessions
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A, B and C can do a work in 6, 8, 12 days respectively. B and C work together for 2 days and then A takes C's place. How long will it take to finish the work? A. 2 days B. 3 days C. 4 days D. 5 days E. 6 days
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Re: A, B and C can do a work in 6, 8, 12 days respectively. B and C work t
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30 Jan 2019, 02:28
Total work to be done = LCM(6,8,12) = 24 units A can do 4 units per day B can do 3 units per day C can do 2 units per day B+C in 1 day = 5 units for 2 days, 10 units will be completed by B and C. Remaining is 14 units. Now A and B work together, They can do 4+3 = 7 units per day. Then 14 units will be completed in 2 days. A is the answer.
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Re: A, B and C can do a work in 6, 8, 12 days respectively. B and C work t
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30 Jan 2019, 02:54
Bunuel wrote: A, B and C can do a work in 6, 8, 12 days respectively. B and C work together for 2 days and then A takes C's place. How long will it take to finish the work?
A. 2 days B. 3 days C. 4 days D. 5 days E. 6 days LCM method is suitable here.
LCM of 6,8,12 =24 units of work.
A's work = 4 units /day B's work = 3 units/days C's work = 2 units/day
(A + C)' 2 days work = 3 +2 = 5 *2 = 10 units.
Remaining Work = 24  10 = 14
14 Units done by (A + B)
(A + B)'s performance in a day = 4 + 3 =7
14/7 = 2 days.
Thus, A and B will take only 2 days to finish the remaining work .
A is the correct answer.



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A, B and C can do a work in 6, 8, 12 days respectively. B and C work t
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30 Jan 2019, 03:00
Bunuel wrote: A, B and C can do a work in 6, 8, 12 days respectively. B and C work together for 2 days and then A takes C's place. How long will it take to finish the work?
A. 2 days B. 3 days C. 4 days D. 5 days E. 6 days rate of B & C = 1/8 + 1/12 ; 5/24 so amount of work done by b & c = 5/24 * 2 = 5/12 work left = 15/12 = 7/12 rate of work of A & B = 1/6+ 1/8 = 7/24 since w=r*t w=7/12 , r = 7/24 t = 24/12 = 2 total work would be finished in 2 days of B& C and 2 days of A & B = 2+2 = 4 IMO C



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Re: A, B and C can do a work in 6, 8, 12 days respectively. B and C work t
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14 Feb 2019, 09:35
I just have one doubt... Is the question asking the total number of days or just the days in which A&b finish the remaining work. If it was total number of days then the answer is 4 days . If the question is asking only the number of days it took A&b to finish the remaining work then the answer is 2 days ..... Which one is the right one. As far as I understood the question, it's asking about the days A&b finished the work, but OA is C.. Can anyone clear my doubt..
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Re: A, B and C can do a work in 6, 8, 12 days respectively. B and C work t
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14 Feb 2019, 09:41
thyagi wrote: I just have one doubt... Is the question asking the total number of days or just the days in which A&b finish the remaining work. If it was total number of days then the answer is 4 days . If the question is asking only the number of days it took A&b to finish the remaining work then the answer is 2 days ..... Which one is the right one. As far as I understood the question, it's asking about the days A&b finished the work, but OA is C.. Can anyone clear my doubt..
Posted from my mobile device thyagiquestion has asked How long will it take to finish the work?which means total days..



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A, B and C can do a work in 6, 8, 12 days respectively. B and C work t
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14 Feb 2019, 11:20
Bunuel wrote: A, B and C can do a work in 6, 8, 12 days respectively. B and C work together for 2 days and then A takes C's place. How long will it take to finish the work?
A. 2 days B. 3 days C. 4 days D. 5 days E. 6 days if given n people finishing a work in k days 1/a + 1/b + 1/c + 1/d + .... + 1/n= 1/k (i.e., 1/k th fraction of work done on each day)
given : 1/a = 1/6 1/b = 1/8 1/c = 1/12 b and c work together for two days each day 1/b+1/c two days 2*(1/b+1/c)a replaces c a and b works for say t days t*(1/a+1/b)the sum all the fractions work done should be one 2*(1/b+1/c) + t*(1/a+1/b) = 12*(1/8 + 1/12) + t*(1/6+1/8) = 1 1/4+1/6+7t/24 = 1 5/12 + 7t/24 = 1 7t/24 = 1 5/12 = 7/12 t = 2 days if the question is asking about the amount of time taken to finish the work after A replaces C Option A  2 days if the question is asking for the total time taken to finish the work 2 + 2 = 4 days Option C  4 days  please leave a kudos




A, B and C can do a work in 6, 8, 12 days respectively. B and C work t
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14 Feb 2019, 11:20






