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2 years ago

What is the value of x in the equation x – y = 30, when y = 15?

2 answers:

6 0

X= 45, you would place 15 into y's place, which would give you x-15= 30... then you would add 15 to both sides, which would give you x=45<span />

Citrus2011 [14]2 years ago

5 0

Hello There :)
This is a simple problem with a simple solution.
First change your variable of y to 30
Then turn the problem around to y + 15
Then you should get a answer of 45
45 would be x
Hope This helped!!!!

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Answer:

A sample of 1068 is needed.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

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We need a sample of n.

n is found when M = 0.03.

We have no prior estimate of $\pi$ , so we use the worst case scenario, which is $\pi = 0.5$

Then

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Step-by-step explanation:

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So, we find the decimal number by separating the parts.

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