Question

if 20 men or 24 women or 40 boys can do a job in 12 days working for 8hours a day.how many men working with 6 women and 2 boys take to do a job four times as big working 5 hours a day for 12 days?

Answer 1

26?

Answer 2

To do the original job, it takes:
Men: 20 men * 96 hours = 1920 man-hours, or
Women: 24 women * 96 hours = 2304 woman-hours, or
Boys: 40 boys * 96 hours = 3840 boy-hours

The new job is 4 times as big, so it will take
Men: 7680 man-hours, or
Women: 9216 woman-hours, or
Boys: 15,360 boy-hours

In 5 days of 12-hour days there are 60 hours of work.
6 women do 6 * 60 hours = 360 woman-hours, and
2 boys do 2 * 60 hours = 120 boy-hours of work

For the new job:
The women did 360/9216 = 0.0390625 part of the new job
The boys did 120/15,360 = 0.0078125 part of the new job

The work left to do is 1 - 0.0390625 - 0.0078125 = 0.953125 part of the job left
for the men to do.

Since the men do the entire new job in 7680 man-hours, 0.953125 part of the job will take 0.953125 * 7680 = 7320 man-hours to do. Since the men can work for 60 hours, 7320/60 = 122. The answer is 122 men.

Answer 3

oops didn't read the "4 times as big part"
26 was the answer if it's the same job,

1/(20*8*12) * n * 5* 12+ 1/(24*8*12) * (6) * 5 * 12 + 1/(40*8*12) * 2*5 * 12 = 4
n = (indeed) 122

Answer 4

given answer is 2mens....

Answer 5

I dont know how it is....

Answer 6

2 men?

Answer 7

that's just impossible even without doing any calculation

Answer 8

maybe they meant 2 Zarkons. Two Zarkons could do the work, but not two regular men.

If you just have regular men then you need 122 of them.

Answer 9

LOL

Answer 10

I'm just stating facts...no jokes here

Answer 11

not sure how many sourwing's it would take...I'll have to think about that

Answer 12

it would take infinite lol

Answer 13

I'm betting somewhere between 2 and 122

Answer 14

you are too modest