A teacher wanted to know how well the gifted students in here class perform relative to her other classes. She administers a standardized test with a mean of 50 and a standard deviation of 10. A student scores of 55, what percent of students have a higher score than hers

30.85%.

Step-by-step explanation:

Let X denotes the score of  random student.

Given: and

We assume that scores are normally distributed.

Then , the probability that a a student score higher than 55:

Hence, the percent of students have a higher score than hers is 30.85%.

the direct variation says that:

then the equation is of the form is given by:

            where k is the constant variation.

from the given table:

consider any value of x and m(x)=y

x = 2 and m(x)=y = 3

substitute these value in [1]; we have;

divide both sides by 2 we get;

⇒

check:

put x = -1 and m(x) = -1.5

substitute in the equation:

-1.5 = -1.5                   true

therefore, the function m(x) represents a direct variation

graph of this function as shown below:

step-by-step explanation: