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AP EAMCET20226 Jul 2022Morning ShiftMathematicsProbabilityActual

A bag contains 21 toys numbered 1 to 21 . A toy is drawn and then another toy is drawn without replacement. The probability that both toys will show even numbers is

Options

  1. A5 21
  2. B3 14
  3. C11 42
  4. D4 21

Correct answer

B. 3 14

Step-by-step solution

Total number of toys numbered from 1 to 21 . P (two toys will show even numbers) == ¹⁰ c ₂ ²¹ c ₂ The total number of even numbers between 1 to 21 is 10. So, = ¹⁰ ~L ₂ ²¹ ~L ₂ = 10 9 21 20 = 8 14 .

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