<h3>
Answer: 7/13</h3>
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Explanation:
We know that the marble selected is red, so we don't need to focus on the other colors.
7 red marbles are in urn B out of 2+7+4 = 13 total red marbles.
The probability the red marble came from urn B is therefore 7/13
25
X x 5 = 125
125/5=x
X=25
