If the job were to be done by 5 men working at double the speed, how long would it take them to finish?

To determine how long it would take 5 men working at double speed to finish the job, it's important to first understand the impact of doubling the speed and increasing the workforce.

Assuming the original job is quantified in terms of hours and manpower, when you increase the worker count to 5 men and assume they are working at double the speed, the overall efficiency increases significantly.

If one man takes a certain amount of time to complete the job at a certain speed, doubling the speed effectively halves the time it takes to do the same job when the same number of men are working. Since there are now 5 men instead of 1, and they are working twice as fast, they combine their efforts to complete the job much quicker. Specifically, the time taken is calculated by considering both the increased speed and the increased number of men.

If the original time taken by 1 man is 'T' hours, at double the speed, it would take him T/2 hours to finish the job. When you have 5 men working at this new speed, the time needed can be divided further by 5.

Thus, if you take T/2 (the time for one man working at double speed) and divide it by 5