The variance of $20$ observations is $5$. If each observation is multiplied by $2$,find the new variance of the resulting observations.

  • A
    $10$
  • B
    $20$
  • C
    $5$
  • D
    $25$

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Difficult
View Solution

The coefficient of variation of the following distribution is
Class interval$0-5$$5-10$$10-15$$15-20$$20-25$
Frequency$4$$1$$10$$3$$2$

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