- If 20 men can build a wall 56 meters long in 6 days.

- Length of a similar wall built by 35 men in 3 days can be figure out in this way.

## Explanation

Three given entities here are

- Men
- Days
- Length of Wall

To determine the relation here, let suppose length of wall built by 35 men in 3 days = y

__Case I__

Men Length of Wall

20 56

35 y

- More men can build longer wall.
- Less men can build a wall but not much longer.

This clearly indicates that there is direct relation.

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

20 : 35 :: 56 : y ________ (i)

__Case II__

Days Length of Wall

6 56

3 y

- More days means more time to build longer wall.
- Less days means little time to build a wall.

This clearly indicates that there is direct relation.

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

6 : 3 :: 56 : y ________ (ii)

By (i) and (ii)

20 : 35 :: 56 : y

6 : 3

35 x 3 x 56 = 20 x 6 x y ________ (A)

After simplifying equation (A), we can easily figure out the value of y (y = 49)

## To Find

Length of wall built by 35 men in 3 days = ?

## Solution

__Method I__

Let suppose

Length of wall built by 35 men in 3 days = y

Men Days Length of Wall

20 6 56

35 3 y

Relation between men and length of wall & days and length of wall is direct so;

20 : 35 :: 56 : y

6 : 3

35 x 3 x 56 = 20 x 6 x y

5880 = 120y

y = 5880/120

y = 49 meters

**Length of wall built by 35 men in 3 days = 49 meters answer**

__Method II__

20 men can build a wall in 6 days = 56 meters

20 men can build a wall in 1 day = 56/6 meters

20 men can build a wall in 1 day = 9.333 meters

1 man can build a wall in 1 day = 9.333/20 meters

1 man can build a wall in 1 day = 0.467 meters

35 men can build a wall in 1 day = 0.467 x 35 meters

35 men can build a wall in 1 day = 16.333 meters

35 men can build a wall in 3 days = 16.333 x 3 meters

35 men can build a wall in 3 days = 49 meters

**Length of wall built by 35 men in 3 days = 49 meters answer**

## Conclusion

If 20 men can build a wall 56 meters long in 6 days, then 49 meters length of a similar wall can be built by 35 men in 3 days.