a group os 30 people can complete a job by working 10 hrs a day in 15 days.the group starts the work.but at the end of every day, starting from the first day, one person leaves the group and the remaining people work for 20 mins less on the next dayQ-on which day will the work be completed ?1-28th 2-29th 3-30th |
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total work = 30x10x15x60 people-minutes
total work according to new condination,
= 30x1x600 + 29x1x580 +28x1x560+ ................ nth day
= 20(302 + 292 +282 +272 + ........... nth term)
30x10x15x60 <or =20(302 + 292 +282 +272 + ........... nth term)
30x10x15x3 < or =(302 + 292 +282 +272 + ........... nth term)
13500 <or =(302 + 292 +282 +272 + ........... nth term)
we know, 12 +22 + 32 + 42 + .................... + 302 = 30x31x61/ 6 = 5x31x61= 9455
LOCHA HAI KUCHH>............
Thanks hamraj your method seems w/o any flaw
I think the question misses the fourth and fifith option which might have the option of a value more than 30
hey bro thx for ur time ur process seems perfect but the ans is 29 i dont know how
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