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CAIE A Level Mathematics 9709 · Discrete random variables

Discrete random variables: calculation question

2 marksFoundation

A machine produces components independently, and each component is faulty with probability 40%40\%. A sample of 100100 components is taken, and XX is the number of faulty components in the sample.

  1. (a)

    Find Var(X)\mathrm{Var}(X).

    [2]

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