# If 45 persons can complete a work in 20 days, then the time taken by 75 persons will be ______ hours.

**Solution:**

__No. of Persons__** **__No. of Hours__

45 20

75 x = ?

The number of persons and number of hours are inversely proportional.

If 75 persons work then the time taken to complete the work will be:

x = 20 × (45/75)

x = 20 × (3/5)

x = 4 × 3

x = 12 days = 12 × 24 = 288 hours

**✦ Try This:** If 75 persons can complete a work in 25 hours, then the time taken by 125 person will be ______ hours.

__No. of Persons__** **__No. of Hours__

75 25

125 x = ?

If 125 persons work then the time taken to complete the work will be:

x = 25 × (75/125)

x = 25 × (3/5)

x = 5 × 3

x = 15 hours

If 75 persons can complete a work in 25 hours, then the time taken by 125 persons will be 15 hours.

**☛ Also Check: **NCERT Solutions for Class 8 Maths Chapter 13

**NCERT Exemplar Class 8 Maths Chapter 10 Problem 41**

## If 45 persons can complete a work in 20 days, then the time taken by 75 persons will be ______ hours.

**Summary:**

If 45 persons can complete a work in 20 days, then the time taken by 75 persons will be 288 hours.

**☛ Related Questions:**

- Devangi travels 50 m distance in 75 steps, then the distance travelled in 375 steps is _______ km.
- Two quantities x and y are said to vary directly with each other if for some rational number k, xy = . . . .
- When the speed is kept fixed, time and distance vary inversely with each other. State whether the st . . . .

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