2 men do?

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2 men do?

by sanju09 » Thu Jan 28, 2010 12:43 am
15 men take 21 days of 8 hours each to do a piece of work. How many days of 6 hours each would 21 women take, if 3 women do as much work as 2 men do?
(A) 18
(B) 20
(C) 25
(D) 27
(E) 30
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by ajith » Thu Jan 28, 2010 12:50 am
sanju09 wrote:15 men take 21 days of 8 hours each to do a piece of work. How many days of 6 hours each would 21 women take, if 3 women do as much work as 2 men do?
(A) 18
(B) 20
(C) 25
(D) 27
(E) 30
Total work = 15*21*8 men hours

= 3/2*15*21*8 women hours

Now with 6 hours and 21 women no of days = 2*15*21*4/6*21 = 20 Days
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by kvamsy » Thu Jan 28, 2010 2:13 am
ajith wrote:
sanju09 wrote:15 men take 21 days of 8 hours each to do a piece of work. How many days of 6 hours each would 21 women take, if 3 women do as much work as 2 men do?
(A) 18
(B) 20
(C) 25
(D) 27
(E) 30
Total work = 15*21*8 men hours

= 3/2*15*21*8 women hours

Now with 6 hours and 21 women no of days = 2*15*21*4/6*21 = 20 Days

I believe answer is E , Can I have OA please

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by thephoenix » Thu Jan 28, 2010 2:21 am
3w=2m----->21w=14m

15*8*21(man hours)=14*6*n(man hours;21 women=14 men)

solving n=30 days

hence E
Oa pls

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by sanju09 » Thu Jan 28, 2010 2:30 am
OA is [spoiler]E[/spoiler]
The mind is everything. What you think you become. -Lord Buddha



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by ajith » Thu Jan 28, 2010 3:04 am
ajith wrote:
sanju09 wrote:15 men take 21 days of 8 hours each to do a piece of work. How many days of 6 hours each would 21 women take, if 3 women do as much work as 2 men do?
(A) 18
(B) 20
(C) 25
(D) 27
(E) 30
Total work = 15*21*8 men hours

= 3/2*15*21*8 women hours

Now with 6 hours and 21 women no of days = 2*15*21*4/6*21 = 20 Days
Now with 6 hours and 21 women no of days = 3*15*21*4/6*21 = 30 Days

Slight calculation mistake :( it is indeed 30 days
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