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3 years ago

When a 49 pound weight is attached to a spring, the spring

Mathematics

1 answer:

lorasvet [3.4K]3 years ago

6 0

im not for sure but I think the answer is 9! my reasoning is below,,

Step-by-step explanation:

$\frac{49}{7} = \frac{63}{x}$

do the crossing method and it would result in this

(49×x) = (63×7)

after simplifying both sides

49x = 441

divide both sides by 49 and the result will be

x = 9 !!

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Step-by-step explanation:

1) 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.

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s represent the sample standard deviation

n represent the sample size

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The confidence interval for the mean is given by the following formula:

$\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}$ (1)

2) Solution to the problem

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