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The marks obtained by 10 students in a Statistics test are 24,47,18,32,19,15,21,35,50 and 41. What is the variance of the largest five observations?

Options

  1. A14.6
  2. B21.8
  3. C25.2
  4. D46.8

Correct answer

D. 46.8

Step-by-step solution

15,18,19,21,24,32,35,41,47,50 Largest 5 observations are 32,35,41,47,50 aligned Mean & = = 32+35+41+47+50 5 & = 205 5 =41 aligned aligned ^2 & = (x_i- )^2 5 & = 9^2+6^2+0^2+6^2+9^2 5 & = 234 5 =46.8 aligned

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