A quality control inspector examined a batch of electronic components and classified each as either defective or non-defective. The frequency table below shows the number of defective components:
| Classification | Frequency |
|---|---|
| Defective | 15 |
| Non-defective | ? |
If the probability of selecting a non-defective component at random from this batch is , what is the total number of non-defective components in the batch?