Q:

A) 21 | B) 20 |

C) 22 | D) None of these |

Answer: B) 20

Explanation:

Explanation:

It is the same as a person with 20 years more age replaces an existing person of the group ( or village)

Since the total age of the village having n persons, is being increased by 20 years and the average age of village is being increased by 1 year, hence there are total 20 people in the village.

**Alternatively : ** ( n x 42 ) + 20 = ( n x 43 )

=> n=20

Q:

Answer

Actual average salary of 12 officers = 400

Total salary of 12 officers = 400 x 12 = 4800

Average of these 12 officers as a whole =60

Total salary of 12 officers as a whole = 60 x 12 = 720

The total salary of rest = 4800 - 720 = 4080

Difference in average of the rest of officers = 60 - 56 = 4

Rest of the officers =

Total number of employees = 1020 + 12 = 1032

42
1200

18
736