Question

12 men working 8 hours a day complete a piece of work in 10 days. To complete the same work in 8 days,working 15 hours,how many men are needed​

Answer 1

Answer:

Step-by-step explanation:

We know this:

12 men : 8 hours/day : 10 days

x men : 15 hours/day: 8 days

Lets try and reduce the number of variables which can be done if we eliminate a common factor between the two.

For this lets see how many days 12 men would take to complete the work if they worked 15 hours instead of 8.

Now we know that if 12 men work harder, they will complete work quicker. So the rate of work and the duration are inversely proportional.

So 8 h/d : 10

15 h/d : y days

Then y = 8 *10/15 = 80/15 = 16/3 days.

Now we can refactor the first set of equations as :

12 : 15 : 16/3

x : 15 : 8

We can eliminate 15 because its the same.

12 : 16/3

x : 8

Since x men take more time than 12 men, x must be lesser than 12.

Therefore

8*x = 12 * 16/3

or

x = 12 * 2/3 = 8 men.

Answer 2

Answer:

Step-by-step explanation: