A student scores 74 on a geography test and 249 on a mathematics test. The geography test has a mean of 80 and a standard deviation of 5. The mathematics test has a mean of 300 and a standard deviation of 34. If the data for both tests are normally​ distributed, on which test did the student score better relative to the other students in each​ class?

Respuesta :

Answer:

In geography test.

Step-by-step explanation:

We have been given that a student scores 74 on a geography test. The geography test has a mean of 80 and a standard deviation of 5. The student scores 249 on a mathematics test. The mathematics test has a mean of 300 and a standard deviation of 34.

Let us find z-scores for both data points. The z-score tells that a data point is how many standard deviation above or below mean.

[tex]z=\frac{x-\mu}{\sigma}[/tex], where,

z = z-score,

x = Sample score,

[tex]\mu[/tex] = Mean,

[tex]\sigma[/tex] = Standard deviation.

[tex]z=\frac{74-80}{5}[/tex]

[tex]z=\frac{-6}{5}[/tex]

[tex]z=-1.2[/tex]

Let us find z-score for mathematics test score.

[tex]z=\frac{249-300}{34}[/tex]

[tex]z=\frac{-51}{34}[/tex]

[tex]z=-1.5[/tex]

Since z-score for geography test is  [tex]-1.2[/tex], so student was 1.2 standard deviation below mean.

Since z-score for mathematics test is  [tex]-1.5[/tex], so student's score was 1.5 standard deviation below mean.

Therefore, the student did better on geography test relative to the other students in each​ class.