30 men working 7 hrs a day can do a piece of work in 18 days. In how many days will 21 men working 8 hrs a day to do same work ?

Question

anonymous · Answer

22.5 days equivalent to 23 days

anonymous · Answer

30  7  18
21  8    ?
now 30 -> 7=  18
       1   -> 7=  18*30
       1   -> 1=  18*30*7
       21 -> 8=  18*30*7/21*8 
==>45/2=22.5

anonymous · Answer

gud ans yaar!
but in detailed ?

anonymous · Answer

ok?

anonymous · Answer

a/b+c/d=b/a+d/c,then prove that a3/b3+c3/d3=b3/a3+d3+c3.r u konw this answer?

anonymous · Answer

no buddy,
i dnt know it !!

anonymous · Answer

30 men works 7 hours daily implies that 30*7 = 210 hrs daily.
In 18 days, that would be 18*210 = 3780 hrs to complete the work.

Now, 21 men works 8 hrs daily implies that 21*8 = 168 hrs daily.
To complete the work now, will take 3780/168 = 22.5 days.

anonymous · Answer

great !!

anonymous · Answer

u want what u want to write with this solotion.sorry

anonymous · Answer

i dnt get u ??
thesujoysaha !!