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MHT CET202410 May 2024Evening ShiftMathematicsStatisticsActual

The mean and variance of 7 observations are 8 and 16 respectively. If first five observations are 2,4,10,12,14 , then absolute difference of remaining two observations is

Options

  1. A1
  2. B2
  3. C3
  4. D4

Correct answer

B. 2

Step-by-step solution

Let the unknown numbers be x and y . Mean =8 aligned & 2+4+10+12+14+x+y 7 =8 & x+y=14 ...(i) & Variance =16 & 2^2+4^2+10^2+12^2+14^2+x^2+y^2 7 & 460+x^2+y^2=7 [16+(8)^2 ] & 460+x^2+y^2=560 & x^2+y^2=100...(ii) aligned Solving (i) and (ii), we get x=6, y=8 or x=8, y=6 Required absolute difference =|x-y|=2

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