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.
Answer:
b
the points make a sad face on the graph and if you do the vertical line test you can see that its a function
Answer:
50
Step-by-step explanation:
35 +15 =50 15 dived by 2 = 7.5 x 2 =15 + 35 = 50
Answer:
13
Step-by-step explanation:
I think yes because the number are not all the same