Question

The average age of 16 students in a college is 20. Out of them, the average age of 5 students is 20 and the average age of the other 10 students is 20.4. Find the age of the 16th college student.

• A. 24
• B. 16
• C. 20
• D. 22

Answer 1

Answer:

B. 16

Solution: Given The average age of 16 student = 20 the average age of 5 student = 20 Formula used Average = Sum of observation/No. of observation Calculation Total age of 16 student = 16 × 20 = 320 ⇒ Total age of 5 student = 5 × 20 = 100 ⇒ Total age of 10 student = 10 × 20.4 = 204 ⇒ Let the age of 16th student be x ⇒ 320 = 100 + 204 + x ⇒ x = 16 ∴ The age of 16th college student is 16.