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3 years ago

I don’t get this one

Mathematics

2 answers:

kvasek [131]3 years ago

5 0

Hiya!

When there are 2 negatives together, the (-) sign changes into a (+) sign.

-7 - (-2.5) ⇒ -7 + 2.5

Your answer is D. -7 + 2.5

(-7 + 2.5 = -5.5)

fomenos3 years ago

4 0

Hi!

Two negatives make a positive, so this can be rewritten as
-7+2.5

The answer is D. -7+2.5

Hope this helps! :)
-Peredhel

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What is -(1)<br>Please help me.

KatRina [158]

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3 years ago

The diameters of bolts produced in a machine shop are normally distributed with a mean of 5.725.72 millimeters and a standard de

suter [353]

Answer:

Top 5% is 5.84 milliters and the bottom 5% is 5.60 millimeters.

Step-by-step explanation:

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this problem, we have that:

$\mu = 5.72, \sigma = 0.07$

Top 5%:

X when Z has a pvalue of 0.95. So X when Z = 1.645

$Z = \frac{X - \mu}{\sigma}$

$1.645 = \frac{X - 5.72}{0.07}$

$X - 5.72 = 1.645*0.07$

$X = 5.84$

Bottom 5%:

X when Z has a pvalue of 0.05. So X when Z = -1.645

$Z = \frac{X - \mu}{\sigma}$

$-1.645 = \frac{X - 5.72}{0.07}$

$X - 5.72 = -1.645*0.07$

$X = 5.60$

Top 5% is 5.84 milliters and the bottom 5% is 5.60 millimeters.

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3 years ago

Which equation could be represented by 5 divided by 1/2 = 10

kkurt [141]

Answer:

Step-by-step explanation:

Here's what you write:

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3 years ago

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Dmitry_Shevchenko [17]

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