18. s = 5r^2 + 7......making r the subject
s - 7 = 5r^2
(s - 7) / 5 = r^2...by taking the sqrt of both sides, it eliminates the ^2
( sqrt (s-7)/5) = r
19. h = ut - 1/2gt^2....u = 100, t = 1 4/5(or 9/5)...g = 6.4
h = (100)(9/5) - 1/2(6.4)(9/5^2)
h = 180 - 1/2(6.4)(3.24)
h = 180 - 3.2(3.24)
h = 180 - 10.368
h = 169.632 or 169 79/125
20. sorry..do not know this one
In statistics, the standard deviation deviation may be a measure of the quantity of variation or dispersion of a group of values. The margin of error may be a statistic expressing the number of sampling error within the results of a survey. The correlation could be a statistical measure of the strength of the connection between the relative movements of two variables.
Given nothing and that we need to explain standard deviation. margin of error, correlation coefficient .
Standard deviation
In statistics, the standard deviation may be a measure of the number of variation or dispersion of a group of values. an occasional variance indicates that the values tend to be near the mean of the set, while a high variance indicates that the values are detached over a wider range.
Formula:
where x bar is mean and N is size of population.
Margin of error
The margin of error may be a statistic expressing the quantity of sampling error within the results of a survey. The larger the margin of error, the less confidence one should have that a poll result would reflect the results of a survey of the complete population.
Formula for M=z*s/
here z is z value of Z score , s is variance , n is that the sample size.
Correlation coefficient
In statistics, the Pearson parametric statistic ― also called Pearson's r, the Pearson product-moment parametric statistic, the bivariate correlation, or colloquially simply because the coefficient of correlation ― could be a measure of linear correlation between two sets of information.
Formula=∑∑∑
Learn more about correlation coefficient at brainly.com/question/4219149
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The answer is d
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Answer:
Buy the batteries and stereo online:
4.99*2= $9.98 +$90 = $99.98
6.99-5.00 = $1.99
99.98+1.99=$101.97
3Cds in store
7.97*3= $23.85
5% tax = 1.19
10% off = 2.39
$23.85 - $1.19= $22.66
22.66 + 101.97= $124.63
All in store:
12+100+23.85= 135.85 - 6.45 = $129.40
All online:
9.98 + 90 + 26.85= 126.85 +$1.99 = 128.84
<u><em>(CREDIT: Hussain514)</em></u>