Answer:
2.28% of tests has scores over 90.
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 have that:
What proportion of tests has scores over 90?
This proportion is 1 subtracted by the pvalue of Z when X = 90. So
has a pvalue of 0.9772.
So 1-0.9772 = 0.0228 = 2.28% of tests has scores over 90.
The discount was 48%. The original price was $28.00, but the new price was $14.60.
Answer:
y=-8
Step-by-step explanation:
First, rewrite the equation in slope-intercept form:
Now just look at the slope-intercept form and your y-intercept is -8, and your slope is .
If you don't know what slope-intercept form is it is y=mx+b where m is your slope and b is your y-intercept.
Hope this helps! :)
Answer:
the answer is647
Step-by-step explanation:
600+30+17