Sue took a test in both biology and math last week. The biology test had a mean of 70 and a standard deviation of 7 whereas the math test had a mean of 75 and a standard deviation of 10. Sue scored a 76 on the biology test and a 76 on the math test. On which test did she do better in comparison to the rest of the class? Select one:a. she did the same on each testb. the math testc. the biology testd. cannot be determined

Question

Mathematics

Edith Compton

2 November, 22:46

Sue took a test in both biology and math last week. The biology test had a mean of 70 and a standard deviation of 7 whereas the math test had a mean of 75 and a standard deviation of 10. Sue scored a 76 on the biology test and a 76 on the math test. On which test did she do better in comparison to the rest of the class? Select one:a. she did the same on each testb. the math testc. the biology testd. cannot be determined

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Answers (1)

Know the Answer?

Aleena Spencer · Answer 1

c. the biology test

Step-by-step explanation:

To answer this problem we need to calculate the z-score of both tests, using the formula:

z = (x - μ) / σ

Where x is Sue's score, μ is the mean, and σ is the standard deviation.

For the biology test, the z-score is:

z = (76 - 70) / 7 = 6/7 = 0.857

For the math test, the z-score is:

z = (76 - 75) / 10 = 1/10 = 0.100

Because the z-score for the biology test is greater than the z-score for the math test, Sue did better in the biology test, in comparison to the rest of the class.