JEE Mains · Maths · STD 11 - 14. probability
In an examination, there are \(10\) true-false type questions. Out of \(10\) , a student can guess the answer of \(4\) questions correctly with probability \(\frac{3}{4}\) and the remaining \(6\) questions correctly with probability \(\frac{1}{4}\). If the probability that the student guesses the answers of exactly \(8\) questions correctly out of \(10\) is \(\frac{27 k }{4^{10}}\), then \(k\) is equal to
- A \(598\)
- B \(487\)
- C \(412\)
- D \(479\)
Answer & Solution
Correct Answer
(D) \(479\)
Step-by-step Solution
Detailed explanation
\(A =\{1,2,3,4\}: P ( A )=\frac{3}{4} \rightarrow \text { Correct }\) \(B =\{5,6,7,8,9,10\} ; P ( B )=\frac{1}{4} \text { Correct }\) \(8\) Correct…
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