Suppose that your statistics professor tells you that the scores on a midterm exam were approximately normally distributed with a mean of 78 and a standard deviation of 7. The top 15% of all scores have
been designated A’s. Your score is 89. Did you earn an A? Explain.

Step-by-step explanation:

z-score representing 85% is 1.04 (from table)

Let x be the score representing the lower limit of 85%.

Use the formula to find z-scores:

We have:

Substitute the values and solve for x:

The lower limit of the top 15% is 85.28.

Since your score is greater than 85.28 you earned an A

y = 5x + 17

step-by-step explanation:

a perpendicular line will be the opposite reciprocal slope of the given equation.   the slope given is -1/5 so the opposite reciprocal is 5

find b:

7 = 5 (-2) + b

7 = -10 + b

17 = b

write equation

y = 5x + 17