A bandleader randomly select's 2 students out of 100 band members. if you and your brother are both bandmembers what is the probability that you are both selected?

Probability of an event happening = (numbers of ways it can happen) / (total numbers of outcomes)

P=probability that we are both selected

P₁=probability that I am selected and my brother is selected after.

P₂=probability that my brother is selected and I am selected afer.

P=P₁+P₂

P₁ = (1/100) * (1/99) = 1/9900

P₂ = (1/100) * (1/99) = 1/9900

P=1/9900 + 1/9900=2/9900≈0,0002≈0.02%

solution: P=2/9900≈0.02%