Question

If it takes 6 men 4 days to dig a hole 3 metres deep, how long will it take 10 men to dig same hole 7 metres deep?

Answer 1

Explanation:

6 men → 4 days → 3 metres

1 man → 24 days → 3 metres

1 man → 8 days → 1 metres

1 man → 56 days → 7 metres

10 men → 5.6 days → 7 metres

therefore, 5.6 days

Topic: direct n inverse proportions

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Answer 2

It will take 5.6 days for the 10 men to dig the same hole 7 m deep.

Explanation:

Laying the data in column

----------------------------------------------------

6 men 3 m hole 4 days

10 men 7 m hole x days

-----------------------------------------------------

As
`6` men dig a hole in
`4` days, so their rate will be:

`rate\:=\:(4)/(3)`

Then
`6` men would take
`7* (4)/(3)=(28)/(3)` days to dig a hole of depth 7 m.

As we are letting 10 men do work, so they would

take
`(6)/(10)* (28)/(3)=(28)/(5)` days.

so

`(6)/(10)* (28)/(3)=(28)/(5)`

`=5.6` days

Therefore, it will take 5.6 days for the 10 men to dig the same hole 7 m deep.