A box contains 2 red, 3 blue, and 5 green marbles. Two marbles are drawn successively with replacement. Find the probability that both drawn marbles are green.
Answer
The correct answer is — Multiply the probabilities of the two independent draws: .
Step-by-step solution
- Calculate the total number of marbles: .
- Find the probability of drawing a green marble in one draw: .
- Because the draws are with replacement, the probability for each draw remains .
- Multiply the probabilities of the two independent draws: .
Common mistake: Treating the draws as without replacement and reducing the denominator after the first draw.
Concept tested: Probability with replacement
Published · How this solution was prepared and checked
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