The mean of 90 items was found to be 45. Later on, it was discovered that two…
2024
The mean of 90 items was found to be 45. Later on, it was discovered that two items were misread as 26 and 19 instead of 62 and 09 respectively. The correct mean is (approximately)
Answer: C. 45.2 — Initial total: 45 × 90 = 4050 Recorded (misread) items: 26 and 19 (sum = 45) Actual items: 62 and 9 (sum = 71) Correction to total: Difference = correct sum −…
- A.
29.4
- B.
30.3
- C.
45.2
- D.
30.1
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Correct answer: C
Initial total: 45 × 90 = 4050
Recorded (misread) items: 26 and 19 (sum = 45)
Actual items: 62 and 9 (sum = 71)
Correction to total:
Difference = correct sum − recorded sum = 71 − 45 = 26
Corrected total = 4050 + 26 = 4076
Correct mean: 4076 ÷ 90 = 45.288888...
Final answer (approx.): 45.29 (≈45.3).
Note: None of the provided options exactly equals 45.29; the closest provided value is 45.2, which is about 0.09 too low.