Answer:
B) 0.11
Explanation:
Use the conditional probability formula.
P(transfer | never graduated) = P(transfer & never graduated) / P(never graduated)
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Denominator
But the P(never graduated) is made of two parts:
P(never graduated) = P(transfer & never graduated) + P(freshman & never graduated)
= (1 -0.80)×(1 -0.85) + (0.80)×(1 -0.70)
= (0.20)(0.15) + (0.80)(0.30)
= 0.0300 +0.2400 = 0.2700
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Numerator
The numerator of our fraction is one of the components we just calculated:
P(transfer & never graduated) = (1 -0.80)×(1 -0.85) = 0.0300
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Conditional Probability
So ...
P(transfer | never graduated) = 0.0300/0.2700 = 1/9 ≈ 0.11