.....plzz help my hw ends at 8:00
2 answers:
You might be interested in
Answer:
y + 9 = - 2(x - 9)
Step-by-step explanation:
The equation of a line in point- slope form is
y - b = m(x - a)
where m is the slope and (a, b) a point on the line
Calculate m using the slope formula
m =
with (x₁, y₁ ) = (9, - 9) and (x₂, y₂ ) = (- 2, 13)
m = =
= - 2
Using (a, b ) = (9, - 9 ) , then
y - (- 9) = - 2(x - 9) , that is
y + 9 = - 2(x - 9)
Answer:
a) 26.76% probability that a student in the psychology department has a score less than 480.
b) 69.73% probability that a student in the psychology department has a score between 480 and 730.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean and standard deviation
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we haev that:
a. Find the probability that a student in the psychology department has a score less than 480.
This is the pvalue of Z when X = 480. So
has a pvalue of 0.2676.
26.76% probability that a student in the psychology department has a score less than 480.
b. Find the probability that a student in the psychology department has a score between 480 and 730.
This probability is the pvalue of Z when X = 730 subtracted by the pvalue of Z when X = 480.
X = 730
has a pvalue of 0.9649.
X = 480
has a pvalue of 0.2676.
0.9649 - 0.2676 = 0.6973
69.73% probability that a student in the psychology department has a score between 480 and 730.