Question

The mean weight of 80 students is 58 kg. After rechecking, it was discovered that the two weights 52 and 68 were misread as 25 and 86. The correct mean is:

• A. 58.11
• B. 58.237
• C. 57.89
• D. 58.72

Hint:

When errors in data are found, adjust the total sum before recalculating the mean.

Answer 1

The Correct Option is A

Given: - Total weight with incorrect data: \[ \text{Total weight} = 80 \times 58 = 4640 \] - Incorrectly recorded weights: \[ 25 + 86 = 111 \] - Correct weights: \[ 52 + 68 = 120 \] Adjusting the total weight: \[ \text{Correct total weight} = 4640 - 111 + 120 = 4649 \] Now, computing the correct mean: \[ \text{Correct mean} = \frac{4649}{80} = 58.11 \]
Thus, the correct answer is 58.11.