Lesson 2: Explore 4 | MoodleHUB 🎓

1. Lesson 2

1.4. Explore 4

Mathematics 20-2 Module 4

Module 4: Statistical Reasoning

Standard deviation, just like the other summary statistics, can be calculated manually or by using technology. Note that for Mathematics 20-2, you are not expected to determine mean and standard deviation manually.

Use the interactive animation titled Spreadsheet to help Jamila’s group use a spreadsheet program to calculate measures of central tendency and dispersion for the statistic quiz marks for Mr. Kong’s Block 1 and Block 4 classes.

A graphing calculator can also be used to calculate mean and standard deviation. Remember that the symbol for mean is and the symbol for standard deviation is σ.

Use the interactive animation Calculator to help Jeff’s group calculate the mean and standard deviation for the statistic quiz marks for Mr. Kong’s Block 4 class.

Jeff entered all of the values in his data set into list 1 in his calculator. Mean and standard deviation can also be determined with graphing technology from a frequency table.

Use the animation Combined Calculations to determine the mean and standard deviation of the combined quiz marks for Block 1 and Block 4 using a graphing calculator.

The keystrokes required to determine the mean and standard deviation on your calculator may be different than those shown in the previous animations. Consult the user manual for your graphing calculator for specific instructions. If you are still having problems obtaining the correct values, contact your teacher.

Sometimes, an entire class may not do well and the mean (class average) is very low—it may even be less than 50%. When this happens, some teachers will adjust all of the class marks by adding 5% to each student’s mark. What effect does this have on the mean and the standard deviation?

Try This 2

Use Adjusting Marks to compare the mean and standard deviation of different data sets.

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