In a Lions Club, 70% of the members are young and 30% of the members are old. The average age of the old members is 40 years and that of the young members is 20 years. What is the average age of all the members (in years)?

Correct option is A

Given:

70% of the members are young, and 30% are old.

Average age of the old members = 40 years.

Average age of the young members = 20 years.

Formula Used:

Average  = $$\frac{\text{ Total sum of value}}{\text{total number of values}}$$​ ​​

Solution:

Let the total number of members be N

Number of young members = 70% of N = 0.7N

Number of old members = 30% of N = 0.3N

Now, the total age of young members = 0.7N × 20 = 14N

The total age of old members = 0.3N × 40 = 12N

Total age of all members = 14N + 12N = 26N

Thus, the overall average age =$$\frac{26N}{N}$$ = 26 years