we have
p (a) =2/5 p(b)=1/4 ( a and b=1/25
Remember that
we know that for two independent events A,B.
⇒ P(A∩B)=P(A)*P(B)
P(A)=2/5 and P(B)=1/4
so
P(A∩B)=(2/5)*(1/4)=2/20=1/10
that means
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