1. Using a standard normal table
Lesson 11.3B
Using a standard normal table

2. Review
The average credit card debit in a survey was found to be $2400 with a standard deviation of $600. a) What is the probability that a person in our survey had over $3000 in debt? b) What is the probability that a person had between $1200 and $3600 in debt?

3. But what if the numbers are not so pretty?
Can you find the probability that a person had less than $4000 in debt? More than $4000 in debt?

4. The table shows the probability that a given score is less than z.

5. Say a toy car goes an average of 3,000 yards between recharges, with a standard deviation of 400 yards
What is the probability that it
will last less than 4000 yards?
b) What is the probability that it will last more than 2500 yards?
c) What is the probability that it will last between 1000 and 5000
yards?

6. A survey was conducted on the number of seals in an area at different times of the year
The results were normally distributed with a mean of 73 and a standard deviation of 10.
What is the probability that less than 50 were observed?
What is the probability that more than 80 were observed?
What is the probability that between 60 and 70 were observed?

7. On your own
A survey of cholesterol levels in women was distributed normally with a mean of 174 and a standard deviation of 16. What is the probability that a woman’s score was over 200?