Misc 6 - Mean, standard deviation of marks obtained by 50 - Co-efficient of variation

Misc 6 - Chapter 15 Class 11 Statistics - Part 2
Misc 6 - Chapter 15 Class 11 Statistics - Part 3


Transcript

Question 1 The mean and standard deviation of marks obtained by 50 students of a class in three subjects, Mathematics, Physics and Chemistry are given below: Which of the three subjects shows the highest variability in marks and which shows the lowest? To compare the variation, we have to calculate coefficient of variation Coefficient of variation(C.V.) = 𝑺𝒕𝒂𝒏𝒅𝒂𝒓𝒅 𝑫𝒆𝒗𝒊𝒂𝒕𝒊𝒐𝒏﷮𝑴𝒆𝒂𝒏﷯ × 100 For Chemistry Mean = 40.9 Standard deviation = 20 CV = 𝑆𝑡𝑎𝑛𝑑𝑎𝑟𝑑 𝑑𝑒𝑣𝑖𝑎𝑡𝑖𝑜𝑛﷮𝑀𝑒𝑎𝑛﷯ × 100 = 20﷮40.9﷯ × 100 = 48.89 So, CVmaths = 28.57, CVphysics = 46.87, Cvchemistry = 48.89 Since chemistry has highest CV, it has highest variability & Mathematics has lowest CV, so it has lowest variability.

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Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.