Answer
$P(\text{Titleist or Maxfli})=0.85$
Work Step by Step
$N(Titleist)=9$, $N(Maxfli)=8$ and $N(Top-Flites)=3$
Let S be the sample space. $N(S)=N(Titleist)+N(Maxfli)+N(Top-Flites)=9+8+3=20$
$P(Titleist)=\frac{N(Titleist)}{N(S)}=\frac{9}{20}=0.45$
$P(Maxfli)=\frac{N(Maxfli)}{N(S)}=\frac{8}{20}=0.40$
The events "Titleist" and "Maxfli" are mutually exclusive, so:
$P(\text{Titleist or Maxfli})=P(Titleist)+P(Maxfli)=0.45+0.40=0.85$
