The average height of females in the freshman class of a certain college has historically been 162.5 centimeters with a standard deviation of 6.9 centimeters. is there reason to believe that there has been a change in the average height if a random sample of 50 females in the present freshman class has an average height of 165.2 centimeters? use a p-value in your conclusion. assume the standard deviation remains the same.

Step-by-step explanation:

Let X be the average height of females in the freshman class.

X is N(162.5, 6.9)

Sample mean = 165.2

Sample size = 50

Since population std deviation is known and n >30 we can use z statistic

Z = (x bar-mu)/Sigma/sqrt n

i.e. Z =

=2.766

Let alpha be 5%

Z critical value for 95% is 1.96

Our test statistic >1.96

p value = 0.001<0.05(our alpha)

Hence reject null hypothesis

The sample mean > the population mean

Alternate hypothesis is true.

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?