COMEDK · Maths · 36. Probability
Five persons \(A, B, C, D\) and \(E\) are in queue of a shop. The Probability that \(A\) and \(B\) are always together is
- A \(\dfrac{2}{5}\)
- B \(\dfrac{1}{4}\)
- C \(\dfrac{3}{5}\)
- D \(\dfrac{2}{3}\)
Answer & Solution
Correct Answer
(A) \(\dfrac{2}{5}\)
Step-by-step Solution
Detailed explanation
The total number of ways to arrange 5 persons \(A, B, C, D, E\) in a queue is \(5! = 120\). To find the number of arrangements where \(A\) and \(B\) are always together, treat \((AB)\) as a single unit. Now, we have 4 units: \((AB), C, D, E\). These 4 units can be arranged in…
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