Question 3

The mean of the test scores is 80.

To find the mean of the test scores 100, 78, 47, 84, 93, and 78, you add all the scores together and divide by the number of scores. The total sum is 480, and when divided by 6, the result is 80.

A) 80

This option is correct as it accurately represents the mean of the given test scores. The calculation involves summing the scores (100 + 78 + 47 + 84 + 93 + 78 = 480) and dividing by the number of scores (6), resulting in 80.

B) 78

Option B is incorrect because it misrepresents the mean. While 78 is one of the scores, it does not reflect the average when considering all the scores together, as evidenced by the calculation leading to 80.

C) 81

Option C is also incorrect. The average of the test scores is determined to be 80, and 81 does not align with the calculated mean from the total sum of the scores divided by their count.

D) 96

Option D is incorrect as well. A mean of 96 would imply that the test scores are significantly higher than the provided values. The calculation explicitly shows that the mean is 80, making this option clearly inaccurate.

Conclusion

The correct answer, 80, is derived from accurate arithmetic of the total test scores divided by the number of scores. All other options fail to reflect the actual mean calculated from the given data, demonstrating a fundamental misunderstanding of how to compute an average.