I am trying to find the probability of P(BnA')

the data given is:

P(A) = 1/3

P(B) = 1/3

P(AnB) = 1/10

My attempt:

P(A') = 1-(1/3) = 2/3

P(BnA')= P(B) * P(A') = 1/3 * 2/3 = 2/9

The reason I think what I did was wrong is because I believe P(AnB) = P(A) * P(B) only applies to independent events. I don't think these are independent since 1/3 * 1/3 does not equal 1/10. I do not know where to go from here.

Thank you in advance!