The mean of five numbers is $$30.$$ If one number is excluded, their mean becomes $$28.$$ The excluded number is :
A.
$$28$$
B.
$$30$$
C.
$$35$$
D.
$$38$$
Answer :
$$38$$
Solution :
Mean of $$5$$ numbers $$= 30$$
$$\therefore $$ Total sum of $$5$$ numbers $$ = 30 \times 5 = 150$$
After excluded one number
Mean of $$4$$ numbers will be $$= 28$$
$$\therefore $$ Total sum of $$4$$ numbers $$ = 4 \times 28 = 112$$
Thus, excluded number
$$=$$ (sum of $$5$$ numbers $$-$$ sum of $$4$$ numbers)
$$= 150 - 112 = 38$$
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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