If the average of 5, 9, k and m is 12. What is the average of k + 7 and m - 3?

Question: If the average of 5, 9, k and m is 12. What is the average of k + 7 and m - 3?

Solution:
Given, the average of 5, 9, k, and m is 12.
Total sum of these 4 numbers = 12 × 4 = 48
So, 5 + 9 + k + m = 48
⇒ 14 + k + m = 48
⇒ k + m = 48 - 14
⇒ k + m = 34

Now, we need to find the average of (k + 7) and (m - 3).
Sum of the two terms = (k + 7) + (m - 3)
= k + m + 7 - 3
= (k + m) + 4
Substituting the value of (k + m):
= 34 + 4 = 38

Average = Sum/2
= 38/2
= 19

∴ The average of k + 7 and m - 3 is 19.

Correct Answer: ক) 19