COMEDK · Maths · 36. Probability
Two numbers are selected at random from integers 1 to 9 .
If their sum is even, what is the probability that both the numbers are odd?
- A \(\dfrac{4}{9}\)
- B \(\dfrac{5}{8}\)
- C \(\dfrac{2}{3}\)
- D \(\dfrac{1}{6}\)
Answer & Solution
Correct Answer
(B) \(\dfrac{5}{8}\)
Step-by-step Solution
Detailed explanation
The set of integers is \(S = \{1, 2, 3, 4, 5, 6, 7, 8, 9\}\). The number of odd integers is \(5\) (1, 3, 5, 7, 9) and the number of even integers is \(4\) (2, 4, 6, 8). The total number of ways to select two distinct numbers from 9 is \(^{9}C_{2} = \dfrac{9 \times 8}{2} = 36\).…
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