P can do a work in 9.5 days. Q can do the same work in 19 days and R can do the same in 28.5 days. Q

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15 Dec 2017 Time and Work

P can do a work in 9.5 days. Q can do the same work in 19 days and R can do the same in 28.5 days. Q and R start the work and leave after 6 days. P finishes the remaining work in X days. What is the value of 2X?

OPtion

1) 5 days
2) 3 days
3) 4 days
4) 5.5 days
5) 4.5 days
6) 2 days
7) 9 days
8) 7 days
9) 1 day
10) None of these

Solution

Amount of work done by Q and R in 6 days = 6*(1/19 + 1/28.5) = 6*((1.5+1)/28.5) = 15/28.5 = 150/285 = 10/19
Amount of work remaining after 6 days = 9/19

Amount of work done by P in 1 day = 1/9.5
So for 1/9.5 work P takes 1 day
Hence for 9/19 work P would take (1/(1/9.5))*9/19 = 4.5 days
So 2X = 4.5*2 = 9

Option 7)

Correct Option: 7 Best Solution (5)

G.S.Kantharao   7 years AGO

P can do in =9.5
Q can do in =19
R can do in 28.5
If Q and R combindly do=1/19 +2/57 =5/57
If they done for 6 days =30/57 work done.
Remaining=27/57
If P completes=27/57×19/2=4.5
Twice=9
Hence the right option is 7👈

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Ayushi Srivastava   7 years AGO

1/19+(1/28.5)=q+r 1 day work
6day work of q &r=(2.5/28.5)*6
Remaining work=1-(6*2.5/28.5)=9/19
Days takw by P =X=9.5*9/19=4.5
2*X=9 days

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Varun   7 years AGO

Q's work per day = 1/19
R's work per day = 1/28.5

Their work for 6 days = (1/19 + 1/28.5) * 6 =10/19

So, remaining work =1-10/19 = 9/19

P's work per day = 1/9
P works for x days...

So 1/9.5 * x = 9/19

Therefore, x = 4.5

And 2x =9 = Option 7)

Like? Yes | No (1)  

Meena   7 years AGO

If the total work involves making of 57 units, then
P can make 6 units in a day
Q can make 3 units in a day
R can make 2 units in a day.
In 6 days, Q & R can make 30 units.
Balance 27 units are made by P in X (4.5 ) Days.
Hence 2X= 2*4.5=9

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prativasahoo   7 years AGO

P & Q's 1day work=(19*28.5)/19+28.5=57/5
p&q's 6 days work=6*57/5=30/57
remaining work=1-30/57=27/57=9/19
P's 1 day work=1/9.5
P can do the remaining work in x days =(9.5)*(9/19)=4.5
so 2x=2*4.5=9

Like? Yes | No (1)