Lesson 2 Just ACT Normal Solidify Understanding
Learning Focus
Interpret standardized test scores that are distributed normally.
How can understanding normal distributions help us interpret test scores and other real-life data?
Open Up the Math: Launch, Explore, Discuss
One of the most common examples of a normal distribution is the distribution of scores on standardized tests like the ACT. In 2010, the mean score was
Why does it make sense that scores are distributed normally on a standardized test?
1.
Use this information to sketch a normal distribution curve for this test.
Use technology to check your graph. Did you get the points of inflection in the right places? (Make adjustments, if necessary.)
2.
In What Is Normal, you learned the
a.
What percentage of students scored below
b.
About what percentage of students scored above
c.
About what percentage of students scored between
3.
Your friend, Calvin, would like to go to a very selective college that only admits the top
Pause and Reflect
4.
Many students like to eat microwave popcorn as they study for the ACT. Microwave popcorn producers assume that the time it takes for a kernel to pop is distributed normally with a mean of
Ready for More?
Here’s a challenge: Estimate the percent of test-takers who scored between
Takeaways
Estimating population percentages from a normal distribution:
Lesson Summary
In this lesson, we sketched a normal distribution and used it to estimate population percentages. We found a process that helps to visualize the region included so that the
1.
You survey
2.
Given: