Question

The results from the last quiz that Mr. Tham gave his class are 10, 15, 25, 75, 75, 77, 80, 83, 85, and 90. Which statistical measure makes these scores seem low overall?

Answer 1

Answer:

The mean.

Step-by-step explanation:

There are three basic statistical measures: the mean, the median and the mode.

Mean is what you get when adding all the results from the quiz and then divide this sum you get by the amount of data you have.  Since you have 10 quiz results the mean is:

$Mean = \frac{10+15+25+75+75+77+80+83+85+90}{10}$

$Mean= 61.5$

Mode is the most repeated value in your data. In this case the most repeated value is 75, which appears twice.

The median is the value that separates the higher half from the lower half of your data. Since you have a data sample of 10 you need to add the two values in between the higher and lower half and then divide the sum by two.

10, 15, 25, 75, 75, 77, 80, 83, 85, 90

The values in between the two halves are: 75 and 77. Then the median is:

$Median = \frac{75+77}{2}$

$Median = 76$

Since mean is the lowest of the statistical measures, this is the one that makes scores seem low overall.

Answer 2

Using average makes these scores seem overall low: because it you add them up and divide them by the quantity you get 61.5 as the average which is low for a quiz grade