AI Chapter 7 Review: Descriptive Statistics

The marks achieved by seven students in a class test are 4, 7, 6, 10, 8, 8, and 3.

Without using that statistics features of a graphing calculator, find the mean.

• 6.50

• 6.57

• 7.0

• 7.67

The marks achieved by seven students in a class test are 4, 7, 6, 10, 8, 8, and 3.

Without using that statistics features of a graphing calculator, find the median.

• 6

• 6.57

• 7

• 8

The marks achieved by seven students in a class test are 4, 7, 6, 10, 8, 8, and 3.

without using the features of a graphing calculator, find the mode.

• 6

• 7

• 8

• 10

The marks achieved by seven students in a class test are 4, 7, 6, 10, 8, 8, and 3.

Use a graphing calculator to find the standard deviation.

• 2.26

• 2.44

• 6.0

• 6.57

The marks achieved by seven students on a class test are 4, 7, 6, 10, 8, 8, and 3. The mean is 6.57 and the standard deviation is 2.26.

The teacher increases all marks by 2. Without using a calculator, state the new mean and the new standard deviation.

• Mean = 6.57 and Standard deviation = 4.26

• Mean = 8.57 and Standard deviation = 2.26

• Mean = 8.57 and Standard deviation = 4.26

• There will be no change.

A group of students were asked how many books they have read in the last two months. The results are shown in the table.

How many students were surveyed?

A group of students were asked how many books they have read in the last two months. The results are shown in the table.

Use your graphing calculator to determine the mean number of books read by the students. Give your answer to 2 decimal places.

A group of students were asked how many books they have read in the last two months. The results are shown in the table.

Use your graphing calculator to find the standard deviation. Give your answer to 2 decimal places.

A pharmaceutical company has developed a new drug to decrease cholesterol. The final stage of testing is to compare the new drug to their current drug. They have 150 volunteers, all recently diagnosed with high cholesterol, from which they want to randomly select a sample of 18. However, they require that, as close as possible, 20% of the sample be below the age of 30, 30% to be between the ages of 30 and 50 and 50% to be over the age of 50.

State the name of this type of sampling technique.

• Simple Random Sampling

• Stratified Random Sampling

• Systematic Sampling

• Convenience Sampling

Half of the 18 volunteers who are selected by the pharmaceutical company in Question 9 are given the current drug and half are given the new drug. After six months each volunteer has their cholesterol level measured and the decrease in their cholesterol is shown in the table.

Find the mean decrease in cholesterol for volunteers using the new drug. Give your answer to two decimal places.