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AP EAMCET20228 Jul 2022Evening ShiftMathematicsProbabilityActual

Three unbiased coins are tossed. Then, the probability of getting at most two heads is

Options

  1. A3 / 4
  2. B1 / 4
  3. C3 / 8
  4. D7 / 8

Correct answer

D. 7 / 8

Step-by-step solution

3 unbiased coins are tossed. Sample space, S= HHH, HHT, HTH, HTT, THH, THT, TTH, TTT n(S)=8 Let E be the event of getting at most two heads. E^ = HHH P(E)=1-P (E^ )=1- n (E^ ) n(S) =1- 1 8 = 7 8

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