Question

One man can do a piece of work in 3 hours; another can do the same piece of work in 2 hours . How long will they take if they work together.​

Answer 1

Answer:

First man will take 3 hours and the second man will take 2 hours to do the work. The question do not says that they work together. If we assume that they do the same work together, the calculations would be:

First man uses 3 hours to complete 1 work

So, in 1 hour, he does 1/3 of the work.

Similarly, second man uses 2 hours to complete 1 work

So, in 1 hour, he does 1/2 of the work.

If the both work together, in 1 hour they would be able to complete: 1/3 + 1/2 of the total work.

So, in 1 hour they would complete 5/6 of the work.

So, they would complete the entire work in 1/(5/6) hours

= 6/5 hours

= 1.2 hours

= 1 hour and (0.2*60) minutes

= 1 hour and 12 minutes.

If it was a basic mathematics question, the above answer would be correct, however, in practical, it is possibly different than the above calculations. There are several factors that needs to be taken into account. For example, if the man is working alone, he won’t have to waste time in conversations and gossips, which he might do while working with the second man. Also, if the work can only be done using 1 person, having the second man is a waste of resource. So, the time needed would be equal to the first man or the second man’s job, depending upon who is doing it. Moreover, some work needs 2 or more man to complete, and if a person is doing it alone, he is probably wasting excessive time to do the job. 2 man together may be able to do the above work in as less as 20 minutes.