The average of 10 observations is 40. It was realised later that an observation was misread as 33 in place of 50. Find the correct average.​

Correct option is D

Given:

Average of 10 observations = 40

One value misread as 33 instead of 50

Find the correct average

Formula Used:

Sum = $$\text{Average} \times \text{Number of observations}$$​​

Corrected Sum = Wrong Sum - Wrong Value + Correct Value

Correct Average =$$\dfrac{\text{Corrected Sum}}{\text{Number of observations}}$$​​

Solution:
Wrong Sum = 10$$\times$$​40 = 400
Corrected Sum = 400 - 33 + 50 = 417
Correct Average = $$\dfrac{417}{10} = 41.7$$​​