A bag holds 3 red and 2 blue balls. Two are drawn without replacement. What is P(both red)?
Answer and explanation
Correct answer: C. 3/10
- Step 1: First red: 3/5. Step 2. Second red with 4 left, 2 red: 2/4. Multiply: 6/20 = 3/10. Answer: 3/10. Why not the others: 9/25 treats the draws as independent (with replacement), 3/5 is one draw and 1/10 is P(both blue).
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