A survey was conducted on preferred modes of transport for different age groups. The table shows the number of respondents for two age groups and their preferred transport.
| Preferred Transport | Under 30 | 30 or Older |
|---|---|---|
| Car | 25 | 40 |
| Public Transport | 15 | x |
| Bicycle | 10 | 5 |
If a randomly chosen respondent who is 30 or older prefers public transport with a probability of , what is the value of ?
