Question

In: Statistics and Probability

Raul received a score of 79 on a history test for which the class mean was...

Raul received a score of 79 on a history test for which the class mean was 70 with a standard deviation of 5. He received a score of 70 on a biology test for which the class mean was 70 with standard deviation 6. On which test did he do better relative to the rest of the class?

Expert Solution

Solution :

Given that ,

mean = = 70 ( history)

standard deviation = = 5

x = 79

Using z-score formula,

z = x - /

z = 79 - 70 / 5

z = 1.80 ( history)

mean = = 70 ( biology)

standard deviation = = 6

x = 70

Using z-score formula,

z = x - /

z = 70 - 70 / 6

z = 0 ( biology)

History test did he do better relative to the rest of the class, because history test z-score 1.80 larger than biology test z-score 0.

orchestra answered 2 years ago

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