The average of 7 numbers is found to be 25. Later, it was found that two…
2026
The average of 7 numbers is found to be 25. Later, it was found that two numbers 29 and 12 were wrongly copied as 10 and 10. The correct average is:
- A.
25
- B.
27
- C.
28
- D.
29
Attempted by 23 students.
Show answer & explanation
Correct answer: C
Step 1: Calculate the initial sum.
Initial sum = Average × Count = 25 × 7 = 175.
Step 2: Adjust the sum.
Corrected sum = Initial sum - (Sum of incorrect values) + (Sum of correct values)
Corrected sum = 175 - (10 + 10) + (29 + 12)
Corrected sum = 175 - 20 + 41 = 196.
Step 3: Find the correct average.
Correct average = Corrected sum / Count = 196 / 7 = 28.
Final Answer: Option 3