The average of 5 consecutive even numbers is A. If next 5 even numbers are also included, then what is the average of these 10 numbers?

Explanation

Given: The average of 5 consecutive even numbers is A Calculation: Let X is an even number. So 5 five consecutive even numbers = X, X + 2, X + 4, X + 6 and X + 8 Avg = [5X + (2 + 4 + 6 + 8)] /5 = X + 4 = A and if the next five even numbers X + 10, X + 12, X + 14, X + 16 and X + 18 are also included then Average will become = [10X + 2(1 + 2 + ... + 9)]/10 = (10X + 90) / 10 = X + 9 = A + 5 Hence, A + 5 is the correct answer.