IBM Developer interview questions

Technical questions all over the place, the interviewers are very nice though. Questions involved toss coins, the probability of two boys if one of them is a boy. How to calculate the conditional probability of xxx if conditioning on xxx?

They sent me an email and schedule a phone call interview, and it took about half an hour for the interview, some basic resume questions and ask me to describe the most impressing projects that have ever done, and then some questions on the projects that they will do.