- Download the worksheet to save time writing
- Start solving the practice problems
- If you're stuck, watch the video solutions
- See your summary to get more insights

Find the -score that corresponds to the following percentile:
In a survey of weekly hours spent on online courses by a group of students, the following hours were reported: , , , , , , , , , , , and . Calculate the -score for the student who spent the most hours online.
Determine the probability that a standard normal variable is less than .
The heights of adult male giraffes in a wildlife reserve are bell-shaped with a mean of feet and a standard deviation of feet. A particular giraffe is measured at feet. Calculate the -score for this giraffe's height and determine if it is unusual.
The figure below shows the continuous uniform distribution of customer waiting times at a coffee shop. Determine the mean and standard deviation for the distribution of the waiting times.
If a problem asks for the probability that z is less than a certain value, which tail is being referenced?
A TI-84 Plus (not CE) only accepts left-tail areas. You are given P(z > b) = 0.30. What area should you input to find z?
The distribution of ages for marathon winners in a certain city is approximately bell-shaped, with a mean of years and a standard deviation of years. In , the winner was years old. Find the -score for this age and state whether it is unusual.
What are the mean and standard deviation of the standard normal distribution?
In a survey of employees, the highest monthly salary recorded was . The mean monthly salary was with a standard deviation of . What is the -score for the highest salary? Express your answer with two decimal places.