What's the probability of living if you had a brain tumor?

It varies: There are several types of brain tumors. The grade of the tumor determines the prognosis. Low grade gliomas (as these tumors are called) are indolent, patients can live for a very long time. High grade tumors(called glioblastoma multiforme) are more dangerous and can be fatal in a large majority of patients. Ask your oncologist or neurosurgeon to educate you about your situation.

Depends: Survival after a diagnosis of 'brain tumor' depends heavily on the type of tumor as well as on treatment. Some benign tumors are associated with long life after surgical removal; some malignant tumors kill within about a year or so of initial diagnosis, and there is a whole range from rapid death to long survival.