hi
Ans. of urs 2nd question
it's an invitation bt as soon as u collect the ticket by paying consideration it become the contract between the contractee nd contractor (means between u nd applicable authority of that bus)
Not necessary.
First answer to 2nd question
If a bus is standing at bus station it is an invitation to offer. If some goes in it i.e. enjoy benefit from it then it becomes bound to bus company with implied contract.
Now 1st question
collateral contract to illegal contract not neccesary be illegal....
for e.g. If A says to B that if he kill C then i will give you 10000Rs. It is an illegal agreement and is punishable by indian penal code.
Now If A borrows 10000 rs. from Z to give it to B to kill C then this contact is collateral to illegal agreement hence void and Z can't recover that money from A but this contract became void but was not illegal..
Plz correct me if my explanation is wrong...