18.X.4. Examples

Try these first

1. 1.

   What is the probability of getting exactly 2 heads when tossing a coin 4 times?

   Hint

   Remember to define n, k, and p before calculating.

2. 2.

   A factory produces 90% defect-free products. What is the probability that out of 10 products, exactly 9 are defect-free?

   Hint

   Use the PMF formula to solve this.

3. 3.

   What is the PMF formula for the Binomial Distribution?

   Hint

   Think about how to express combinations and probabilities.

4. 4.

   Is it true that the Binomial Distribution can only have two outcomes?

   • True
   • False

   Hint

   Remember the definition of a Bernoulli trial.

5. 5.

   In a city, 30% of the population is a smoker. If we survey 15 people, what is the probability that exactly 5 are smokers?

   Hint

   Use the binomial probability formula and remember to calculate the binomial coefficient.

6. 6.

   A basketball player has a free throw success rate of 75%. If he takes 20 shots, what is the probability that he scores exactly 15 times?

   Hint

   Keep track of your n, k, p, and q when calculating.