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3 men 6 days: 6 men 3 days: 12 men 1.5 days

going the other way...

3 men 6 days: 1.5 men 12 days: 0.75 men 24 days

do it by thirds instead of halves and you have your answer ...easy!

The answer is now obvious. Look!!

3 men 6 days: 6 men 3 days: 12 men 1.5 days

going the other way...

3 men 6 days: 1.5 men 12 days: 0.75 men 24 days

do it by thirds instead of halves and you have your answer ...easy!

The answer is now obvious. Look!!

This of course makes the assumption that the men are working independently and do not gain a synergistic advantage (e.g. by each specialising in different jobs or doing work that one man cannot do alone) by working together and nor do they become redundant when there is more than one person working (e.g. because one job which only needs one man needs to be completed before the other men can do anything useful).

As a ratio exercise it is likely that this assumption is desired, but in real life would be less likely to hold true.

This of course makes the assumption that the men are working independently and do not gain a synergistic advantage (e.g. by each specialising in different jobs or doing work that one man cannot do alone) by working together and nor do they become redundant when there is more than one person working (e.g. because one job which only needs one man needs to be completed before the other men can do anything useful).

As a ratio exercise it is likely that this assumption is desired, but in real life would be less likely to hold true.

So if 3 men take 6 days to build the driveway it would take 3 times as long for just one man to complete the same job i.e. 18 days. 2 men can work twice as fast as one, so they will complete the job in half the time that one man can, so your answer is 9 days. Hope this helps :-)

So if 3 men take 6 days to build the driveway it would take 3 times as long for just one man to complete the same job i.e. 18 days. 2 men can work twice as fast as one, so they will complete the job in half the time that one man can, so your answer is 9 days. Hope this helps :-)

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