COMEDK · Maths · 36. Probability
A bag contains \((n+1)\) coins. It is known that one of these coins has a head on both sides, whereas the other coins are fair. One of these coins is selected at random and tossed. If the probability that the toss results in heads is \(\dfrac{7}{12}\), then the value of \(n\) is
- A 4
- B 5
- C 2
- D 3
Answer & Solution
Correct Answer
(B) 5
Step-by-step Solution
Detailed explanation
Let \(E\) be the event that the selected coin shows heads. Let \(C_1\) be the event that the two-headed coin is selected, and \(C_2\) be the event that a fair coin is selected. The probability of selecting the two-headed coin is \(P(C_1) = \dfrac{1}{n+1}\). The probability of…
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