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?
Answer & explanation
Correct answer: option 4
Lets X is an even number.
So five consecutive even numbers = X, X + 2, X + 4, X + 6 and X + 8
Average = \(\frac{5X + (2 + 4 + 6 + 8)}{5}\) = X + 4 = A
If next five even numbers X + 10, X + 12, X + 14, X + 16 and X + 18 are also included
Average will become = \(\frac{[10X + 2(1 + 2 +....+ 9)]}{10}\)
⇒ \(\frac{(10X + 90)}{10}\) = X + 9 = A + 5