P can do a work in 12 days. Q can do the same work in 6 days and R can do the same in 8 days. Q and

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27 Apr 2017 Time and Work

P can do a work in 12 days. Q can do the same work in 6 days and R can do the same in 8 days. Q and R start the work and leave after 2 days. P finishes the remaining work in X days. What is the value of X?

OPtion

1) 2 days
2) 2.5 days
3) 3 days
4) 3.5 days
5) 4 days
6) 4.5 days
7) 5 days
8) 5.5 days
9) 6.0 days
10) 10 days

Solution

Amount of work done by Q and R in 2 days = 2*(1/6 + 1/8) = 7*2/24 = 7/12

Amount of work remianing after 3 days = 5/12

Amount of work done by P in 1 day = 1/12
So for 1/12 work P takes 1 day
Hence for 5/12 work P would take (1/(1/12))*5/12 = 5 days

Correct Option: 7 Best Solution (14)

G.S.Kantharao   7 years AGO

P can do in 12days
Q can do in 6days
R can do in 8days
P,Q,R can do in 1 day =1/12, 1/6, 1/8 respectively
Q+R together can do in 1 day 1/6 +1/8 = 7/24
In 2 days they both can do =(7/24)*2 = 14/24
Remaining part = 10/24
1/12 th part P can do in = 1day
Let 10/24 part can do by P in = X days.
X = {1/(1/12)}*10/24
= 12*10/24 = 5 days.
Hence the right option is 7.

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jeet   7 years AGO

Q and R 's 1 day work =(1/6+1/8)=7/24.
work done by Q and R in 2 days= 2*7/24=7/12.
remaining work= 1-7/12=5/12.
so 5/12 work done by P in =12*5/12=5 days
so answer is: 5 days

Like? Yes (1) | No   

Devendra Marghade   7 years AGO

(Q+R)'s 2 days work=2(1/6 + 1/8) = 7/12
So remaining work=1 - 7/12 =5/12
As P requires X days to finish the remaining work, so X(1/12) = 5/12
=> X=(5/12)/(1/12) = 5
Option 7)

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SAYAN CHATTERJEE   7 years AGO

Total work done by Q & R in 2 days = 2*(1/6+1/8)=7/12
so, work left= (1-5/12)= 7/12
now, 7/12 fraction of work can be completed by P in X days.
so, total work can be done by P in 12*X/5 days.
now, 12*X/5= 12
hence, X=5.
Option 7.

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prashanth.k   7 years AGO

The work done by p,q and r in one day respectively are 1/12,1/6 and 1/8
for 2 days q and r work=2(1/6+1/18)=7/12
total work= 2 days of work of q & r+x days of p work
=>7/12+x*(1/12)=1
=>x+7=12
=>x=5 days

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Mukund Manohar   7 years AGO

Work done by P in 1 day = 1/12
Work done by Q in 1 day = 1/6
Work done by R in 1 day = 1/8
Work done by Q and R in 2 days = 2 * {(1/6) + (1/8)}
= 2 * (7/24) = 14/24 = 7/12
Remaining Work = 1- (7/12)
= 5/12
Value of X = (5/12) / (1/12) = 5 days

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Sumit S Chawla   7 years AGO

Remaining work is 5/12 for P. If P works 1/12 per day, So P will be able to complete 5/12 work in 5 days.

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Vengadesh   7 years AGO

P per day work 2,Q per day work 4, R per day work 3.
P,Q and R finish 24 work per day.
initially Q and R per day work is 7,
for 2 days , 7 x 2 = 14...
Remaining work is 10....
Remaining work finished by P...
P's Per day work 2....

P's finish the Remaining 10 work,

10/2 = 5 days....

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Vittesh   7 years AGO

​P can do the work in 12 days
1 days work = 1/12parts
Q can do the work in 6 days
1 days work = 1/6parts
R can do the work in 8 days
1 days work = 1/8parts

Workdone by Q & R in 2 days = (1/6+1/8)*2 = 7/12 parts

i.e. 7y/12 part if total work is y

Reamaining work is y-7y/12 = 5y/12
y work is done by A in 12 days
1 part in 12/y
5y/12 part in 12/y*5y/12= 5

Which is required ans x= 5​

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jyothi chhabria   7 years AGO

p=1/12
q=1/6
r=1/8
2*(q+r)=2*(8/48+6/48)
q+r completed work is 7/12
remaining work done by p is 1-7/12
p need to complete 5/12
p 1 day work is 1/12
So 5/12 work can be done in 5 days

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vaibhav patil   7 years AGO

​P can do the work in 12 days
1 days work = 1/12parts
Q can do the work in 6 days
1 days work = 1/6parts
R can do the work in 8 days
1 days work = 1/8parts

Workdone by Q & R in 2 days = (1/6+1/8)*2 = 7/12 parts

i.e. 7y/12 part if total work is y

Reamaining work is y-7y/12 = 5y/12
y work is done by A in 12 days
1 part in 12/y
5y/12 part in 12/y*5y/12= 5

Which is required ans x= 5

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Vahira Bollina   7 years AGO

(Q+R)'s 1 day work= (1/6 + 1/8)= 7/24
work done by Q and R in 2 days= (7/24)*2=7/12
remaining work=[1-(7/12)]=5/12
now 1/12 work is done by P in 1 day
so,5/12 work is done by P in [12*(5/12)]= 5 days

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B.LAKSHMI ANUSHA   7 years AGO

R+Q=7/24
They work for 2 days=(2)×(7/24) = 14/24
Let total work=1
Remaining work = 1- (14/24) = 10/24 = 5/12
P's one day work is 1/12
Therefore 5 days work of P is 5/12
So, p needs 5 days

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ganesh chemanchula   7 years AGO

Q and R's 2 day work=(1/6+i/8)*2=14/24
Remaining work=1-14/24=10/24 work
p can finish 1 work in 12 days then P can finish 10/24 work in =(10*12)/24=5 days

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