यदि 10 प्रेक्षणों का योग 12 है और उनके वर्गों का योग 18 है, तो मानक विचलन है:

This question was previously asked in
SSC CGL Tier-II (JSO) 2022 Official Paper (Held On: 4 March 2023)
View all SSC CGL Papers >
  1. 4/5
  2. 2/5
  3. 3/5
  4. 1/5

Answer (Detailed Solution Below)

Option 3 : 3/5
ssc-cgl-crash
Free
PYST 1:SSC CGL 2023 - Quantitative Aptitude(Held On:14 Jul 2023 Shift 1)
1.9 Lakh Users
25 Questions 50 Marks 20 Mins

Detailed Solution

Download Solution PDF
सही उत्तर 3/5 है। 
Key Points

मानक विचलन = \(\sqrt{{{(x_i - \bar x)}^2} \over n} = \sqrt {Variance} \) 
इसलिए, प्रसरण V(X) = \({1 \over n} {{(x_i - \bar x)}^2} \)
या, \(\rm v(x)=\frac{1}{n}\left[\Sigma(x_i^2-2\times x_i \times \bar x+\bar x^2)\right]\)

\(\rm =\frac{\Sigma x_i^2}{n}-2 \bar x\left(\frac{\Sigma x_i}{n}\right)+\frac{\Sigma \bar x^2}{n}\)

\(=\rm \frac{\Sigma x_i^2}{n}-2\bar x^2+\frac{n.\bar x^2}{n}\)

\(\rm = \frac{\Sigma x_i^2}{n}-2\bar x^2+\bar x^2\)

\(\rm V(x)=\frac{\Sigma x_i^2}{n}-\bar x^2\)

दिया गया है, 10 प्रेक्षणों का योग 12 है और उनके वर्गों का योग 18 है। 
इस प्रकार, n = 10, \(\sum x_i = 12\)\(\sum x_i^2 = 18\) 
इसलिए, माध्य \(\bar x = 1.2\)
इस सूचना को प्रसरण V (X) के समीकरण में रखने पर, हमें प्राप्त होता है

\(\rm V(x)=\frac{\Sigma x_i^2}{n}-\bar x^2\)

\(=\frac{1}{10}\times 18-(1.2)^2\)

= 1.8 - 1.44

=0.36

इसलिए, अभीष्ट मानक विचलन = 

\(\sqrt {Variance} = \sqrt{(0.36)} = 0.6 = {3 \over 5}\)

 

Latest SSC CGL Updates

Last updated on Jun 9, 2025

-> The SSC CGL Notification 2025 has been released on 9th June 2025 at ssc.gov.in.

-> The SSC CGL exam registration process is now open and will continue till 4th July 2025, so candidates must fill out the SSC CGL Application Form 2025 before the deadline.

-> This year, the Staff Selection Commission (SSC) has announced approximately 14,582 vacancies for various Group B and C posts across government departments.

->  The SSC CGL Tier 1 exam is scheduled to take place from 13th to 30th August 2025.

->  Aspirants should visit ssc.gov.in 2025 regularly for updates and ensure timely submission of the SSC CGL exam form.

-> Candidates can refer to the SSC CGL syllabus for a better understanding of the exam structure and pattern.

-> The SSC CGL Eligibility is a bachelor’s degree in any discipline.

-> Candidates selected through the SSC CGL exam will receive an attractive salary. Learn more about the SSC CGL Salary Structure.

-> Attempt SSC CGL Free English Mock Test and SSC CGL Current Affairs Mock Test.

-> Candidates should also use the SSC CGL previous year papers for a good revision. 

More Variance and Standard Deviation Questions

More Statistics Questions

Get Free Access Now
Hot Links: teen patti yas teen patti joy official teen patti joy teen patti joy apk