Students in a science class roll a model car down a ramp. They repeat this process for 5 trials,

Question

recording the number of whole feet the car travels during each trial in the table below.

The students want to count the first trial as practice and remove its value from the data set. How
will the standard deviation of the data in the table change if they remove the Trial 1 value? Use the
drop-down menus to explain.

Feet
Traveled

Trial 1

3

Model Car Trials

Trial 2

6

Trial 3

Trial 4

7

5

Trial 5

6

Click the arrows to choose an answer from each menu.

The standard deviation of the data will

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if the Trial 1 value is removed. This is

because

Answer 1

To determine how the standard deviation will change if the Trial 1 value is removed, let's analyze the situation.

The recorded distances for the trials are as follows:

• Trial 1: 3 feet
• Trial 2: 6 feet
• Trial 3: 7 feet
• Trial 4: 5 feet
• Trial 5: 6 feet

If Trial 1 (3 feet) is removed, the new data set will be:

• Trial 2: 6 feet
• Trial 3: 7 feet
• Trial 4: 5 feet
• Trial 5: 6 feet

Now, let's summarize the response:

The standard deviation of the data will

• decrease

if the Trial 1 value is removed. This is

• because removing the outlier (3 feet) from the data set will reduce the overall spread of the data, resulting in lower variability and thus a lower standard deviation.

So the completed statement will be:

The standard deviation of the data will decrease if the Trial 1 value is removed. This is because removing the outlier (3 feet) from the data set will reduce the overall spread of the data, resulting in lower variability and thus a lower standard deviation.