Question

Here are the math test scores of 10 randomly selected students from Class 1 and Class 2.

This table displays the math test scores of 10 randomly selected students from Class 1 and Class 2.
Class 1: 75 80 84 79 92 86 88 86 86 90
Class 2: 83 85 91 93 72 85 76 80 82 89
Find the mean score of each sample. Based on the mean, which class generally performed better on the math test? Express your answer as a decimal. Do not round your answer. 

Answer 1

To find the mean score of each class, you can use the formula for the mean, which is the sum of all scores divided by the number of scores.

**Class 1 scores:**
75, 80, 84, 79, 92, 86, 88, 86, 86, 90

First, we calculate the sum of Class 1 scores:

\( 75 + 80 + 84 + 79 + 92 + 86 + 88 + 86 + 86 + 90 = 84 + 79 + 92 + 86 + 88 + 86 + 86 + 90 = 540 \)

Now, find the mean for Class 1:

Mean for Class 1 = \( \frac{540}{10} = 84.0 \)

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**Class 2 scores:**
83, 85, 91, 93, 72, 85, 76, 80, 82, 89

Now, calculate the sum of Class 2 scores:

\( 83 + 85 + 91 + 93 + 72 + 85 + 76 + 80 + 82 + 89 = % [3+1]83 + 85 + 91 + 93 + 72 + 85 + 76 + 80 + 82 + 89 = 60 + (3 + 1 + 85 + 91 + 93 + 72 + 85 + 76 + 80 + 82 + 89) + = 860 \)

Now, find the mean for Class 2:

Mean for Class 2 = \( \frac{860}{10} = 86.0 \)

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**Comparison of means:**

- Mean score of Class 1 = 84.0
- Mean score of Class 2 = 86.0

Based on the mean scores, Class 2 generally performed better on the math test, with a mean score of 86.0 compared to Class 1's mean score of 84.0.