Question 80

The mean of 30 values was 150. It was detected on rechecking that one value 165 was wrongly copied as 135 for the computation of the mean. Find the correct mean.

Solution

Mean of 30 values = 150

After replacing 135 by 165, correct mean = $$\frac{(30\times150)+(-135+165)}{30}$$

= $$150+\frac{30}{30}=151$$

=> Ans - (A)

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