Need help with probability homework! (Bayesian model)?

[Johnny S]

1. Suppose a pill exists with the property that one out of every 100 such pills contains a lethal amount of a substance, and that the other 99 are harmless.
a. Calculate how many people would be expected to die if:

a 1000 people each take 1 pill,
if 1000 people each take 2 pills,
and if 1000 people each take 100 pills.

Assume each person is taking the pills from a huge source of pills, so that the “1 out of 100” statistic remains unchanged as the pills are taken.

Okay, for the first one, I assumed 1/100 chance of death. Since its taken with replacement, the answer = 1/100 * 1000 people = 10 people will die.

For the second one, Probability of getting pill on first try OR second try. P(A) or P(B) = P(A) + P(B) = 1/100 + 1/100 = 2/50 * 1000 = 20 people will die.

What happens if everyone takes 100 pills?! It seems like everyone is going to die!
Thank you so much! I actually did get 19.9 deaths for 2 pills, but I thought it was wrong, so I started to do it another way.

(:! Thanks again!

-Johnny