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3 years ago

11

The sum of negative eighteen and a number is eleven. what is the number? which equation could be used to solve the problem? x -

18 = 11 18 - x = 11 -x 18 = 11 x 18 = 11 user: solve for y. y - 12 = -10 y = 22 y = -22 y = -2 y = 2

1 answer:

Zepler [3.9K]3 years ago

3 0

Sum means addition
negative 18 means -18
a number can be x
Sum of negative 18 and x should be 11
thus the equation is
$-18+x=11$

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Step-by-step explanation:

Previous concepts

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.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

$\bar X$ represent the sample mean

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Solution to the problem

Part a

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For this case we can calculate the mean like this:

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Part b

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