Question

Some Male and Female labourers were hired for the construction of dam. Five male or 8 female can built a wall of 100 meter in 10 days. Find the time period consumed by 10 men and 16 women to build a 800 meter long wall of a dam.
1. 20 days
2. 22 days
3. 30 days
4. 28 days

Answer 1

Correct Answer - Option 1 : 20 days

Given∶

Five male or 8 female can built a wall of 100 meter in 10 days.

Formula Used∶

A concept of Unitary method.

Calculation∶

According to question, 8 women = 5 men

So, 16 women = 10 men

Also, 10 men + 16 women = 10 men + 10 men = 20 men

A wall of 100 m is built by 5 men in 10 days

A wall of 100 m is built by 1 man in (10 × 5) days

A wall of 1 m is built by 1 man in (10 × 5)/ 100 days      [less length less days]

A wall of 800m is built by 1 man in [(10 × 5 × 800) / 100] days       [ more length more days]

A wall of 800m is built by 20 men in [(10 × 5 × 800) / (100 × 20) = 20 days

∴ They will consume 20 days.