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In tossing three coins at a time, what is the probability of getting at most one head?

Options

  1. A3 8
  2. B7 8
  3. C1 2
  4. D1 8

Correct answer

C. 1 2

Step-by-step solution

aligned & P = P (x=0)+ P (x=1) & = ^3 C₀ ( 1 2 )^3 ( 1 2 )^0+ ^3 C₁ ( 1 2 )^2 ( 1 2 )^1 & =1 1 8 +3 1 8 = 1 2 aligned

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