Verified Solution • 2025–26 Session moderate

QJEEM19Ma6334: JEE Main 2019 Mathematics - Class 11 JEEM19Ma6334 Solution: The mean and the variance of five observations are 4 and 5.20,…

The mean and the variance of five observations are 4 and 5.20, respectively. If three of the observations are 3, 4 and 4 ; then the absolute value of the difference of the other two observations, is :

Multiple Choice Options

  • A 1
  • B 7
  • C 3
  • D 5

Step-by-Step Verified Solution

mean x― = 4, σ2 = 5.2, n = 5, . x1 = 3 x2 = 4 = x3

∑xi=20

x4 + x5 = 9 . . . . . . (i)

∑xi2x−(x―)2=σ⇒∑xi2=106

x42+x52=65 . . . . . .(ii)

Using (i) and (ii) (x4 − x5)2 = 49

|x4−x5|=7

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