Answer:
3
Step-by-step explanation:
The answer for part a would be 130
the answer for part b would be 60
Answer:
4/20=1/5
Step-by-step explanation:
3x + 4y > 12 <span>will have a shaded area below the boundary line</span>
Recalling that SAT scores are always expressed as multiples of 10, then the points we get on the test will be 628.
<h3>What do you mean by standard deviation?</h3>
In statistics, Standard deviation is a measure of the variation of a set of values.
σ = standard deviation of population
N = number of observation of population
X = mean
μ = population mean
WE have been given that SAT scores are normally distributed, with a mean of 500 points and a standard deviation of 100 points.
The solution as follows;
Let be X: scores of SAT
P(X ≥ x) = 0.9
P((X - 500)/100 ≥ (x - 500)/100) = 0.9
P(Z ≥ z) = 0.9
z = 1.28
1.28 = (x - 500)/100
128 + 500 = x
x = 628
Recalling that SAT scores are always expressed as multiples of 10, then the points we get on the test will be 628.
Learn more about standard deviation and variance:
brainly.com/question/11448982
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