Answer:
The percentage of students who scored below 620 is 93.32%.
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 question, we have that:

Percentage of students who scored below 620:
This is the pvalue of Z when X = 620. So



has a pvalue of 0.9332
The percentage of students who scored below 620 is 93.32%.
<span>-5p^3(4p^2 + 3p - 1) = -20p^5 - 15p^4 + 5p^3
answer is
A. first one
</span>-20p^5 - 15p^4 + 5p^3
Answer:
5
Step-by-step explanation:
21-6=15/3=5
Answer:
28
Step-by-step explanation:
P(red marbles) = 3/7
no. if red marbles = 12
12/x = 3/7
3x = 12 x 7
3x = 84
x = 28
the total number of marbles are 28.
hope it helps .
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