Browse by Stream
QnA
Home
Search for Exam, Articles, Questions
QnA
get app
Go To Your Study Dashboard
  1. Home
  2. How to solve this problem- A student scores the following marks in five tests : 45,54,41,57,43. His score is not known for the sixth test. If the mean score is 48 in the six tests, then the standard deviation of the marks in six tests is:
# Engineering

A student scores the following marks in five tests : 45,54,41,57,43. His score is not known for the sixth test. If the mean score is 48 in the six tests, then the standard deviation of the marks in six tests is:

 

  • Option 1)

    \frac{10}{\sqrt{3}}

  • Option 2)

    \frac{100}{3}

  • Option 3)

    \frac{10}{3}

  • Option 4)

    \frac{100}{\sqrt{3}}

 

Answers (1)
S solutionqc

Let score of 6th test be x

then, \frac{45+54+41+57+43+x}{6}=48

x=48

\sigma ^{2}=\frac{\sum \left ( x_{i} - \overline{x} \right )^{2}}{n}

\sigma ^{2}=\frac{3^{2}+6^{2}+7^{2}+9^{2}+5^{2}+0^{2}}{6}=\frac{200}{6}=\frac{100}{3}

\sigma ^{2}=\frac{100}{3}\Rightarrow \sigma =\frac{10}{\sqrt{3}}

correct option (i)


Option 1)

\frac{10}{\sqrt{3}}

Option 2)

\frac{100}{3}

Option 3)

\frac{10}{3}

Option 4)

\frac{100}{\sqrt{3}}

Similar Questions

Preparation Products

Knockout JEE Main April 2021 (One Month)

An exhaustive E-learning program for the complete preparation of JEE Main..

₹ 14000/- ₹ 6999/-
Buy Now
Knockout JEE Main April 2021

An exhaustive E-learning program for the complete preparation of JEE Main..

₹ 22999/- ₹ 14999/-
Buy Now
Test Series JEE Main April 2021

Take chapter-wise, subject-wise and Complete syllabus mock tests and get in depth analysis of your test..

₹ 6999/- ₹ 4999/-
Buy Now
Knockout JEE Main April 2022

An exhaustive E-learning program for the complete preparation of JEE Main..

₹ 34999/- ₹ 24999/-
Buy Now
JEE Main Rank Booster 2021

This course will help student to be better prepared and study in the right direction for JEE Main..

₹ 13999/- ₹ 9999/-
Buy Now
Boost your Preparation for JEE Main 2021 with Personlized Coaching
Start Now
 
Exams
Articles
Questions