Answer
No. see explanations.
Work Step by Step
Given P(A) = 0.42, P(B) = 0.38, and P(A or B) = 0.70.
P(A or B)=P(A)+P(B)-P(A and B) or 0.70=0.42+0.38-P(A and B)
we have P(A and B)=$0.10\ne0$
So A and B are not mutually exclusive.
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