Subtraction: 57 - 28 = ? Show how to solve it step by step.

What two numbers equal 9 and multiply to 16

Artemon [7]

So 3x3 is equal to 9 but i do not understand what you mean and multiply to 16

4 0

2 years ago

A group of 3 children and 2 adults pay a total of $120 to take a karate class. A group of 5 children and 1 adult take the same k

sleet_krkn [62]

Answer:

215

Step-by-step explanation:

8 0

2 years ago

Thompson and Thompson is a steel bolts manufacturing company. Their current steel bolts have a mean diameter of 139 millimeters,

FinnZ [79.3K]

Answer:

0.4010 = 40.10% probability that the sample mean would differ from the population mean by more than 0.8 millimeters

Step-by-step explanation:

To solve this question, we need to understan the normal probability distribution and the central limit theorem.

Normal probability distribution:

Problems of normally distributed samples are 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.

Central limit theorem:

The Central Limit Theorem estabilishes that, for a random variable X, with mean $\mu$ and standard deviation $\sigma$ , the sample means with size n of at least 30 can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$

In this problem, we have that:

$\mu = 139, \sigma = 6, n = 40, s = \frac{6}{\sqrt{40}} = 0.9487$

Either the sample mean differs by 0.8 mm or less from the population mean, or it differs by more. The sum of these probabilities is decimal 1.

Probability it differs by less than 0.8mm

pvalue of Z when X = 139 + 0.8 = 139.8mm subtracted by the pvalue of Z when X = 139 - 0.8 = 138.2 mm

X = 139.8

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

By the Central Limit Theorem

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

$Z = \frac{139.8 - 139}{0.9487}$

$Z = 0.84$

$Z = 0.84$ has a pvalue of 0.7995

X = 138.2

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

$Z = \frac{138.2 - 139}{0.9487}$

$Z = -0.84$

$Z = -0.84$ has a pvalue of 0.2005

0.7995 - 0.2005 = 0.5990

What is the probability that the sample mean would differ from the population mean by more than 0.8 millimeters?

p + 0.5990 = 0.4010

0.4010 = 40.10% probability that the sample mean would differ from the population mean by more than 0.8 millimeters

7 0

2 years ago

Which of the following is the rational exponent expression of third root of 4 n? A) (4n)3

zhuklara [117]

You have to check which of the following expressions is the rational exponent expression of third root of 4n, or mathematically, $\sqrt[3]{4n} .$ Consider all cases: