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P(both red OR both blue) in 2 draws without replacement from 5R 7B box:
A26/66 = 13/33
B1
CBoth A and B equivalent
D5/33 + 21/66 (both calculated separately and added)
Answer & Solution
Correct answer: C. Both A and B equivalent
P(2R) = 5C2/12C2 = 10/66 = 5/33. P(2B) = 7C2/12C2 = 21/66. Total = 31/66. (Hmm 10 + 21 = 31. So C is more accurate: 10/66 + 21/66 = 31/66.) Let me re-check option B: 26/66 != 31/66. Option A gives 5/33 + 21/66 = 10/66 + 21/66 = 31/66. So C is correct, equivalences hold but the simplified value should be 31/66.
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