Average age of group A of 10 students is 20 years. Average age of group B of 20 students is 'x' years. Combined average age of group A and group B is 34 years. What is the value of 'x'?
Show answer & explanation
Correct answer: B
Explanation
Given:
Students in Group A = 10, Average age = 20
Students in Group B = 20, Average age = x
Combined average age = 34
According to the formula:
Combined Average = (Sum of total ages) / (Total students)
Total age of Group A = 10 × 20 = 200
Total age of Group B = 20 × x = 20x
Total students = 10 + 20 = 30
(200 + 20x) / 30 = 34
200 + 20x = 1020
20x = 820
x = 41