Chapter 5 Basic Principles of Probability.

1. Find the probability that the number obtained when a die is rolled is an odd number.

1. Which of the following values cannot be a probability? Select all that apply.

1. -0.05
2. 0.5
3. 1.09
4. 0
5. 1
6. 25%

1. Julie and Scott each toss a coin. What is the probability that they both obtain heads?

1. A teacher asks 25 of her students to write down their favorite color. The results are presented below:

Color frequency

Red 13

Blue 12

Green 5

If a student is selected at random from the above group, what is the probability that this student likes the red color?

1. The table below shows students distribution per grade in a school.

Grade frequency

1 50

2 45

3 40

4 42

5 38

6 55

If a student is selected at random from this school, what is the probability that this student is in fifth grade?

1. Chris Paul of the Los Angeles Lakers had a free throw percentage of 90% in the 2014-15 regular season. If he has 10 free throw attempts, what is the probability he will make all 10?

1. In a clinical trial, researcher found that a certain drug had a 8% chance of curing a known disease. If 7 people are known to have the disease what is the probability of 2 being cured?

1. For a certain type of smart phone the length of time between charges of the battery is normally distributed with a mean of 50 hours and a standard deviation of 15 hours. John owns one of these smart phones and wants to know the probability that the length of time between charges will be between 50 and 70 hours.

1. The time taken to fully service a car at XYZ garage is a random variable having a normal distribution of 20 hours and a standard deviation of 2 hours. What is the probability that a car can be fully serviced in this garage in less than 19.5 hours?