Answer
$.3875$
Work Step by Step
If the download was neither tropical nor regional, it was either pop/rock or urban.
We are interested in the event $E=${pop/rock,urban}
The sample size is $N=400$, The frequency of $E$ is $fr(E)=130+25=155$
The relative frequency of $E$ is $P(E)=\frac{fr(E)}{N}=\frac{155}{400}=.3875$
