# Question on work done by #x# machines in some days?

##### 1 Answer

Option C

#### Explanation:

Given that the initial estimated count of machines be

Given that the adjusted count of machines is

Given that the new count of days to complete the task is 12 days.

Let the amount of work be measured in 'machine days'.

So the amount of work to complete the work is:

Set

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Not 3 but only 1 additional machine is used.

The total amount of work still needs to be done to complete the task.

Let the new count of days be

Using

Divide both sides by

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Set the value of

Thus we have:

This matches option C