Three companies $\text{X, Y}$ and $\text{Z}$ supply computers to a university. The percentage of computers supplied by them and the probability of those being defective are tabulated below
$$\begin{array}{|c|c|c|} \hline \text{Company} & \% \text{ of computers supplied} & \text{Probability of being defective} \\ \hline \mathrm{X} & 60 \% & 0.01 \\ \hline \mathrm{Y} & 30 \% & 0.02 \\ \hline \mathrm{Z} & 10 \% & 0.03 \\ \hline \end{array}$$
Given that a computer is defective, the probability that it was supplied by $\text{Y}$ is
- $0.1$
- $0.2$
- $0.3$
- $0.4$