The first time the band leader selects one member, the probability that either you or your brother gets selected would be 2 out of 80 or in fraction 2/80.
Now, once one of you gets chosen, for the next selection, there are only 79 members left and the probability that the remaining one (between you and your brother) gets selected after is 1/79.
So, if you are both to be selected, the combined probability for that to happen will be (2/80)(1/79) = 1/3160.
Therefore, the answer is 1/3160<span>.</span>
58 stamps is the number she gets each week. So if she went for one week, 58*1=58. 58*2=116 and so on. Because we don't know the exact number of weeks, we say 58w or 58*w because you multiply however many number of weeks she collects.
