The average of a group of men is increased by 5 years when a person aged of 18 years is replaced by a new person of aged 38 years. How many men are there in the group? Choices.
A) 3
B) 4
C) 5
D) 6
E) 7
Solution: Let N be the no. of persons in the group.   Required number of person is given by;   Member in group* aged increased = difference of replacement   N*5 = 38-18   Or, 5N = 20   Or, N = 4.   Answer: Option 4
<result>B</result>
The average of a group of men is increased by 5 years when a person aged of 18 years is replaced by a new person of aged 38 years. How many men are there in the group?