Answer :
First, notice that we have the results of 45 surveys, then, if A is the event {the customer is pleased} and B is the evente {the customer purchased a Toes Knows shoes}, then their probabilities are:
[tex]\begin{gathered} P(A)=\frac{10+7}{45}=\frac{17}{45} \\ P(B)=\frac{3+7+10}{45}=\frac{20}{45} \end{gathered}[/tex]then, the probability that both A and B occur is:
[tex]P(A\cap B)=P(A)\cdot P(B)=\frac{17}{45}\cdot\frac{20}{45}=\frac{340}{2025}=\frac{68}{405}[/tex]therefore, the probability that a random selected customer is pleased and purchased a Toes Knows shoe is 68/405