The mean weight per student in a group of seven students is $$55\,kg.$$ If the individual weights of six students are $$52,\,58,\,55,\,53,\,56$$ and $$54,$$ then the weight of the seventh student is :
A.
$$55\,kg$$
B.
$$60\,kg$$
C.
$$57\,kg$$
D.
$$50\,kg$$
Answer :
$$57\,kg$$
Solution :
The total weight of seven students is
$$55 \times 7 = 385\,kg$$
The sum of the weights of six students is
$$52 + 58 + 55 + 53 + 56 + 54 = 328\,kg$$
Hence, the weight of the seventh student is
$$385 - 328 = 57\, kg.$$
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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