JEE Mains · Maths · STD 12 - 13. probability
Box \(I\) contains \(30\) cards numbered \(1\) to \(30\) and Box \(II\) contains \(20\) cards numbered \(31\) to \(50 .\) A box is selected at random and a card is drawn from it. The number on the card is found to be a non-prime number. The probability that the card was drawn from Box \(I\) is
- A \(\frac{8}{17}\)
- B \(\frac{2}{3}\)
- C \(\frac{4}{17}\)
- D \(\frac{2}{5}\)
Answer & Solution
Correct Answer
(A) \(\frac{8}{17}\)
Step-by-step Solution
Detailed explanation
Let \(\mathrm{B}_{1}\) be the event where Box-I is selected. \(\mathrm{B}_{2} \rightarrow\) where box-II selected \(P\left(B_{1}\right)=P\left(B_{2}\right)=\frac{1}{2}\) Let \(\mathrm{E}\) be the event where selected card is non prime. For \(\mathrm{B}_{1}:\) Prime numbers :…
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