In how many days will 12 men working 8 hours a day plough the same field?
2006-12-20 18:43:52 · 13 answers · asked by raj_paragon 1 in Science & Mathematics ➔ Mathematics
Do this way
30 men working 6 hours/day ploughs a field in 56 days
1 men working 6hours/day ploughs a field in 56X30 days (1 men needs more time)
1 men working 1hour/day ploughs a field in 56X30X6 days (working lees will ask for more time)
12 men working 1 hour/day ploughs a field in (56X30X6)/12 days (increase in no of people will reduce the no of days)
12 men working 8hours/day ploughs a field in (56X30X6)/(12X8) days = 105 days
(increase in working hours further reduce the time needed to do the same job)
so answer is 105 days ........ cool :)
2006-12-20 18:50:08 · answer #1 · answered by TJ 5 · 2⤊ 0⤋
First let's determine the part of field can one man plough in 1 hour
If they work 56 days 6 hours a day that means that they work 336 hours to plough the field
So that means that 30 men in one hour can plough 1/336 of the field
Furthermore we get that one man in one hour can plough 1/(336 * 30) of the field
now if we have 12 men working they can plough 12/(336 * 30) of the field equals 1/(28 * 30)
so if they work 8 hours a day that means that 12 men can plough 8/(28 * 30) of the field in a day equals 1/105 of the field
So to plough the whole field 12 men working 8 hours a day need 105 days
2006-12-21 02:55:13 · answer #2 · answered by N.math 2 · 0⤊ 0⤋
30 men working 6 hours a day can plough a field in 56 days
thus 30 men working 8 hours a day can plough a field in : 8 * 56 / 6 =224/3 days
so 12 men working 8 hours a day can plough a field in 12 * 224/3 / 30 = 29.9
so 12 men working 8 hours a day can plough a field in nearly 30 days
2006-12-21 02:50:30 · answer #3 · answered by James Chan 4 · 0⤊ 2⤋
30 x 6 x 56 = 10080 man hours to plough the field
12 men working eight hours a day = 96 hour.
The total hours is 10080
Divide 10080 by 96 to fihd the days
10080 / 96 = 105
The answer is: It will take 12 men working eight hours a day a total of 105 days to plough the field.
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2006-12-21 04:52:19 · answer #4 · answered by SAMUEL D 7 · 0⤊ 0⤋
Total manhours = 30*6*56 = 10,080
10,080/12/8 = 105 days
2006-12-21 03:18:30 · answer #5 · answered by Helmut 7 · 0⤊ 0⤋
it takes 30 x 6 x 56 man hours to plow the field 10080
so it will take 12 x 8 x Y days to equal 10080
Y = 10080 / 96 = 105 days
2006-12-21 02:48:22 · answer #6 · answered by ignoramus 7 · 0⤊ 0⤋
30
2006-12-21 03:09:22 · answer #7 · answered by dvs 1 · 0⤊ 2⤋
105
2006-12-21 02:57:52 · answer #8 · answered by Anonymous · 0⤊ 0⤋
105 days
30x6=180 man hrs per day.
180x56= 10080 man hours to plow the field.
12x8= 96 man hours per day.
96 divided into 10,080=105 days
2006-12-21 02:50:56 · answer #9 · answered by James M 5 · 0⤊ 0⤋
105 days
2006-12-21 02:53:46 · answer #10 · answered by sweet bhullar 2 · 0⤊ 0⤋