1) A lotery has 1,000,000 tickets and draws 100 tickets to award prizes. How many tickets would you expect to have to purchase before you would win a prize?

2) Lesley claims she can roll triples with three dice in fewer than 20 rolls.
a)what is the expected number of rolls that it would take to roll the first set of triples?
b)what is the probability that she will roll the triples in fewer than five rolls?

Thanks for your help!

2 answers

1. p=0.0001
q=0.9999

P(x)=0.9999/0.0001
1. p=0.0001
q=0.9999

P(x)=0.9999/0.0001
=9999