The average score on a standardized test is 750 points with a standard deviation of 50 points. What is the probability that a student scores more than 700 on the standardized test?

Respuesta :

34.1% is the correct answer

Answer: 0.8413

Step-by-step explanation:

Given : The average score on a standardized test is [tex]\mu=\text{750 points }[/tex]

Standard deviation : [tex]\sigma=50\text{ points}[/tex]

Let x be the score of randomly selected student.

The z-score for standardized test :-

[tex]z=\dfrac{x-\mu}{\sigma}[/tex]

For x= 700

[tex]z=\dfrac{700-750}{50}=-1[/tex]

The p-value = [tex]P(x>700)=P(z>-1)[/tex]

[tex]1-P(z<1)=1-0.1586553=0.8413447\approx0.8413[/tex]

Therefore, the probability that a student scores more than 700 on the standardized test = 0.8413