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MHT CET2016MathematicsProbability

Probability of guessing correctly atleast 7 out of 10 answers in a "True" or "False" test is = ______

Options

  1. A11 64
  2. B11 32
  3. C11 16
  4. D27 32

Correct answer

A. 11 64

Step-by-step solution

P x ≥ 7 = P x = 7 + P x = 8 + P x = 9 + P x = 10 = 10 C 7 1 2 7 1 2 3 + 10 C 8 1 2 8 1 2 2 + 10 C 9 1 2 9 1 2 1 + 10 C 10 1 2 10 11 64

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