"We cannot solve our problems with the same thinking we used when we created them."
- Albert Einstein
15.
10 women can complete a work in 7 days and 10 children take 14 days to complete the work. How many days will 5 women and 10 children take to complete the work?
[A].
3
[B].
5
[C].
7
[D].
Cannot be determined
[E].
None of these
Answer: Option D
Explanation:
1 woman's 1 day's work =
1
70
1 child's 1 day's work =
1
140
(5 women + 10 children)'s day's work =
5
+
10
=
1
+
1
=
1
70
140
14
14
7
5 women and 10 children will complete the work in 7 days.
10 women can do the work in 7 days
why can't 5 women can do the work in 7/2 days
I solved it this way and it is not working...
what goes wrong in the middle??
5 women one days' work = 1/(7/2) = 2/7
10 children one days' work = 1/14
2/7 + 1/14 = 98/35??
Pranathi said:
(Tue, May 31, 2011 01:59:23 PM)
@Manikandasenthil;
when u do 7/2 u r not decreasing the no of women working , but u r decreasing the work they do.
just use a simple logic........... when u reduce the no of people wrking the time taken to complete it will increase.......... in that case when u do 7/2 it either appears that the wrk done is reduced to half or, that u hav doubled the no of women wrking.......
Pranil said:
(Thu, Jun 2, 2011 06:58:00 AM)
Yes this is a good ans.
Ali Umar said:
(Wed, Aug 3, 2011 12:46:29 PM)
Thanks.
Samy super mind.
Asha said:
(Fri, Sep 16, 2011 06:48:02 PM)
Well 10 women can complete a work in 7 days and 10 children can do it in 14 days, that means one woman is 2 times efficient than a child therefore 1woman=2 children, therefore 10 children+10 children(or 5 women) can do a work in 14/2 i.e. 7 days.
Karthik Kovai said:
(Thu, Feb 2, 2012 11:58:30 AM)
Let simply
x be the woman's 1 day work.
y be the children's 1 day work.
so,
10x= 1/7 ; 10y= 1/14
x= 1/70 ; y= 1/140
then 5*1/70 = 1/14 ; 10*1/140 =1/14
1/4 + 1/4 =1/7
So they will take 7 days to complete.
5 women and 10 children will complete the work in 7 days.