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3 years ago

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The ordered pairs (6,8), (9, 12), (x, 20), (18, y) represent a proportional relationship. Find the value of X and the value of Y

. Select the two correct answers.

1 answer:

sasho [114]3 years ago

7 0

Answer:

x=15 y=24

Step-by-step explanation:

This is because the rule is x goes up 3 y goes up 4

(9,12)->(x,20)

it skips one, so instead of adding 3 we add six

x=15

(15,20)->(18,y)

you follow the rule and 4.

Y=24

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Let's define the random variable, $X =$ "Comprehensive strength of concrete". We have information that $X$ is normally distributed with a mean of 2500 psi and a standard deviation of 50 psi (or a variance of 2500 psi). In other words, $X \sim N(2500, 2500)$ .

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Step-by-step explanation:

Notation and definitions

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A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

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