The equation is 30 x 6 x x = 39 x 5 x 12 not clear to understand.
Please explain it clearly. When I solved this problem I got equation as 39 x 12 x 5 = 30 x x x 6.
How come you got that equation?
Jeyan said:
(Thu, Oct 14, 2010 09:41:15 PM)
Ya. Right. Even I got so!
Why not we say 39 persons did work in (12*5) hours.
Then what would be 30 persons working for (x*6) hours ?
Rahul said:
(Thu, Oct 28, 2010 03:46:12 AM)
I always solve this as a work and time problem:
39 people working 5 hours a day finished 1/12th the work in 1 day.
39 people will therefore finish 1/60th (1/12 x 1/5) the work in 1 hour.
1 person will finish (1/60 x 1/39)th the work in 1 hour
So 30 people working for 6 hours will finish:
(1/60) x (1/39) x 6 x 30 = everything cancels out and you are left with 1/13th.
So: 30 people working for 6 hours will finish 1/13th the work in a day meaning they will take 13 days to finish.
Miyyapuram said:
(Tue, Jan 18, 2011 01:46:38 PM)
Ny cross multiplication method i didn't get correct ans.....
39---->12*5hrs
then 30---->x*6hrs
Now 30*12*5=39*x*6
then 30*12*5/39*6=x......... then i got 100/13........
is it correct or wrong
Pratswinz said:
(Sat, Jul 9, 2011 12:18:18 PM)
Hope you all understand....
First codition=total hours to complete the work=39 persons * 12 days * 5 hr
Second codition=total hours to complete the work=30 persons * x days * 6 hr
since the work is still the same so
39*12*5=30*x*6
x=13
Adeel Jabbar said:
(Fri, Aug 26, 2011 12:06:21 PM)
I thing the easy way to solve this out is below.
39 12 5
30 x 6
after cross multiplication, we will have
39 1
3 x
According to rule
39x = 3
x = 3 / 39
now due to indirect relation we will change the above equation as::: x = 39/3 which results ===13
Thanks
Simha said:
(Mon, Dec 26, 2011 03:18:40 PM)
There is simple formula for this type of questions:
M1D1H1 M2D2H2
------ = ------
W1 W2
Where,
M = No.of Men
D = No.of Days
H = No.of Hours
W = Amt of Work done.
30 x 6 x x = 39 x 5 x 12
x =