"Suppose exam scores are normally distributed with a mean of 70 and a standard deviation of 6. The probability that someone scores between a 70 and a 90 is:"

The probability is 0.40824

Step-by-step explanation:

To find this probability, we shall start with finding the z-scores of each

Mathematically;

z-score = (x-mean)/SD

for 70

z = (70-70)/6 = 0

For 90

z = (90-70)/6 = 20/6 = 10/3 = 1.33

So the probability we want to find is;

P(0 < x < 1.33)

we can use the standard normal distribution to get this;

Mathematically, that would be;

P( x <1.33) - P( x < 0)

Using the standard normal distribution table, we have;

P = 0.40824

step-by-step explanation:

i think something is missing in your question because y-1=(x-12) would not pass through the point (-4,-3). because if you replace x by -4 your are supposed to find y=-3 which is not the case her. if you replace x by -4 you find =-15.

i assume the right equation is y-1=1/4*(x-12) because this one is passing through both your points (if you are interested to know how i found that out i can tell you).

in this equation if i replace x by -4 i find y=-3 and if i replace x by 12, i find y=1 so the line representing this equation is passing through those 2 points.

then the standard form of the equation is finding an expression of y in function of x

y-1=1/4*(x-12)

y=x/4-3+1

y=x/4-2

hope that .

do you confirm there was a mistake in the question?

42

step-by-step explanation: