JEE Main · 2024 · 31 Jan 2024 · Shift 1 · Probability

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Two marbles are drawn in succession from a box containing 10 red, 30 white, 20 blue and 15 orange marbles, with replacement being made after each drawing. Then the probability, that first drawn marble is red and second drawn marble is white, is

(A) $\frac{2}{25}$
(B) $\frac{4}{25}$
(C) $\frac{2}{3}$
(D) $\frac{4}{75}$ ✓ Correct

Answer: (D)

Solution

Total marbles

= 10 + 30 + 20 + 15 = 75

. With replacement, the two draws are independent:

P (red then white) = \frac{10}{75} \times \frac{30}{75} = \frac{2}{15} \times \frac{2}{5} = \frac{4}{75}

JEE Main · 2024 · 31 Jan 2024 · Shift 1 · Single correct option

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