9(3j-6) = 27j - 54
<span>Note: a(b-c) = ab - ac</span>
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:
2.50$ off or 22.50$
Step-by-step explanation:
Answer:
-16
Step-by-step explanation:
So let’s solve for 7x. So 7x=34. So 7x-50 is 34-50 or -16
Answer:
1/18
Step-by-step explanation:
1/6 * 1/3
1 *1 = 1
6 * 3 = 18
1/18