Statistics
Geometric and Negative Binomial
1. An oil company conducts a geological study that indicates that an
exploratory oil well should have a 20% chance of striking oil. What is the
probability that the first strike comes on the third well drilled?
2. What is the probability that the third strike comes on the seventh well
drilled?
3. What is the probability that your first 6 kids are 2 boys and 4 girls, not
necessarily in that order?
4. There is a 60% chance of rain for the foreseeable future. What is the
probability that the first time it rains is on the third day?
5. Ten percent of babies are left handed. How many babies must be born
before the probability of having 5 left handed babies is greater than 75%?
6. You are playing roulette and keep betting on black with a probability of
18/38. You decide you are going to quit playing after losing 10 times. What
is the probability that you quit after the 23rd game?
7. If you throw two dice and want to get a 8 what is the probability that you
get the first 8 on the seventh roll? What is the probability that you get one
by the 10 roll?