First let's find the outcomes that are divisors of 3.
The divisors of 3 are 1 and 3, so we will need the probabilities of the outcomes 1 and 3.
The probability of outcome 1 is 0.15, and the probability of outcome 3 is 0.03, so the probability of event A, which includes the outcomes 1 and 3, is the sum of these probabilities:
[tex]\begin{gathered} P(A)=P(1)+P(3) \\ P(A)=0.15+0.03 \\ P(A)=0.18 \end{gathered}[/tex]