The average age of 6 members of a family is 20 years. If the age of the servant is included, then the average age increase by 20 percent. What is the age of the servant?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 48 years.
Given that
The average age of the 6 family members = 20
Average = sum of observations / number of observations
20 = sum of the age of 6 members / 6
⇒ Sum of the age of 6 members = 120
When the servant joins, the sum = 120 + age of servant
New average = 1.2 × 20 = 24
Hence, 24 =
⇒ Age of servant = 168 - 120 = 48