How is electrical eng. branch in iit bombay if my favorite subject is maths?
It depends on you .
Most of them. people I met have taken IIT Bombay electrical engineering just for the sake of giving proper respect to their JEE rank.
There's a friend of mine who did so and now wants to connect with his passionate subject through doing minors.
And yes IIT provides you a great deal of comfort and opportunities to do inter-disciplinary courses.
But at the time you are selecting a discipline in IIT. Most of the people are clueless. So they end up taking according to their ranks.
But if you are passionate about some branch, be it metallurgy, don't worry about your rank just take it.
And though tough you always have an option of branch change if you just hate your branch (but that's always the last option )
Finally, if you want to select a branch do it on the basis of the liking you may have for that branch (if you are clueless you may see what courses are offered or ask someone in that branch regarding the branch)
But don't ever choose any branch based on the
the package you may get else life may become very difficult and unwilling during your job years