The mean income of a group of $$50$$ persons was calculated as $$Rs.\,169.$$ Later it was discovered that one figure was wrongly taken as $$134$$ instead of correct value $$143.$$ The correct mean should be (in $$Rs.$$ ) :
A.
$$168$$
B.
$$169$$
C.
$$168.92$$
D.
$$169.18$$
Answer :
$$169.18$$
Solution :
$$\eqalign{
& {\text{Given,}}\,169 = \frac{{\sum x }}{{50}} \cr
& {\text{Correct value is }}143 \cr
& {\text{Hence, sum is short by }}9 \cr
& \therefore \,M = \frac{{169 \times 50 + 9}}{{50}} = 169 + \frac{9}{{50}} = 169.18 \cr} $$
Releted MCQ Question on Statistics and Probability >> Statistics
Releted Question 1
Select the correct alternative in each of the following. Indicate your choice by the appropriate letter only.
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