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MHT CET202416 May 2024Evening ShiftMathematicsStatisticsActual

The mean and variance of seven observations are 8 and 16 respectively. If five of the observations are 2,4,10,12,14 , then the product of remaining two observations is

Options

  1. A45
  2. B44
  3. C48
  4. D40

Correct answer

C. 48

Step-by-step solution

Let the unknown numbers be x and y . aligned & Mean =8 & 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 aligned -( mean )^2=16 aligned & 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 Product =48

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