Q24 of 55 Page 1

The probability of guessing the correct answer to a certain question is (x/12). If the probability of guessing the wrong answer is (3/4), find x.

If a student copies the answer, then its probability is (2/6). If he doesn’t copy the answer, then the probability is (2y/3). Find the value of y.


If he does not copy the answer, which moral value is depicted by him?

Probability of guessing the correct answer = (x/12)


Probability of guessing the wrong answer = 3/4


Now,


Probability of guessing the correct answer + Probability of guessing the wrong answer = 1


∴ (x/12) + 3/4 = 1


⇒ x/12 = 1 - 3/4


⇒ x/12 = 1/4


⇒ x = 12/4


⇒ x = 3


Probability of copying = (2/6)


Probability of not copying = 2y/3


Now,


Probability of copying + Probability of not copying = 1


∴ (2/6) + (2y/3) = 1


⇒ 2y/3 = 1 – 2/6


⇒ 2y/3 = 2/3


⇒ y = 1


If the student does not copy, then honesty and truthfulness towards his studies is reflected.


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