Sampling and estimation — practice question

The playground equipment includes swings ($S$), roundabouts ($R$), climbing frames ($C$) and play-houses ($P$). The quantities of equipment in each of $3$ playgrounds are listed below: Playground $X$: $3S, 2R, 4P$; Playground $Y$: $6S, 3R, 1C, 2P$; Playground $Z$: $8S, 3R, 4C, 1P$. Every day Nur takes her child to one of these playgrounds. The chance that she goes to playground $X$ is $\frac{1}{4}$. The chance that she goes to playground $Y$ is $\frac{1}{4}$. The chance that she goes to playground $Z$ is $\frac{1}{2}$. On arrival, she selects one item of equipment at random.