sarvajeet

• Apr 11th, 2006

 

total hours taken by 30 men are 20*9

=180*30

=5400

40*x=5400

x=135 hrs

=135/24

=5 days

Naveen Kumar Tiwari

• Apr 19th, 2006

 

a work completed by 30 mens and 20 days to take 9 hours a day

"       "                   1"               "                 "  9*30*20hours a day

  40mens complete this work in 20days by spent (9*20*30)/(40*20)=6.75 hours a day              

kavita kaur

• Nov 23rd, 2006

 

formula: (M*w)/t=(m*w)/t

(30*20)/9=(40*20)/x

where x is no: of hours to work per day

x=12 hrs

bonvamsi

• Feb 27th, 2007

 

here the no. of days taken by 30 men is immaterial 2 us...we are concerned only with the no. of men and the working hrs

                   40:30 :: 9:x   [ where x is the no. of hrs taken by 40 men ]
                   40/30 = 9/x
                   40*x = 9*30
                   x = 6.75 hrs