# Some Persons can Do a Piece of Work in 12 Days. Two Times the Number of Such Person will Do Half of that Work in?

### Computer MCQs Series for PPSC, FPSC – Most Repeated MCQs | Set 6

• Some persons can do a piece of work in 12 days.
• Days taken by two times the number of such person to do half of the work will be figure out in this way.

## Explanation

Two given entities here are

• Person
• Days

To determine the relation here, let suppose; Days taken by two times the number of such person to complete the work = y

Case

Let suppose

Some persons = 10

Two times the number of such person = 20

Person        Days

10               12

20              y

• More persons mean less days.
• Less persons mean more days.

This clearly indicates that there is inverse relation.

Direct/Indirect relation tells how the equation will be written.

10 : 20  ::  y : 12 ________ (i)

20 x y = 10 x 12 ________ (A)

After simplifying equation (A), we can easily figure out the value of y (y = 6 and to do half of the work = 6/2 = 3 days)

## To Find

Days taken by two times the number of such person to do half of the work = ?

## Solution

### Method I

Let suppose

Days taken by two times the number of such person to complete the work = y

Person        Days

10               12

20              y

• Relation between person and days is inverse.

So

10 : 20  ::  y : 12

20 x y = 10 x 12

20y = 120

y = 120/20

y = 6 days

Days taken by two times the number of such person to complete the work = 6 days

Days taken by two times the number of such person to do half of the work = 6/2

Days taken by two times the number of such person to do half of the work = 3 days answer

### Method II

Let suppose

Some persons = 10

Two times the number of such person = 20

Days taken by 10 persons to complete the work = 12 days

Days taken by 1 person to complete the work = (12 x 10) days

Days taken by 1 person to complete the work = 120 days

Days taken by 20 person to complete the work = 120/20 days

Days taken by 20 person to complete the work = 6 days

Days taken by two times the number of such person to complete the work = 6 days

Days taken by two times the number of such person to do half of the work = 6/2

Days taken by two times the number of such person to do half of the work = 3 days answer

### Conclusion

Some persons can do a piece of work in 12 days. Two times the number of such person will do half of that work in 3 days.