Anand needs to hire a plumber. He's considering a plumber that charges an initial fee of $65 along with an

A certain manufacturing procedure produces items that have a mean weight of 55 pounds and a standard deviation of 3.2 pounds. Wi

Mama L [17]

Answer:

99,7 %

Step-by-step explanation:

P [ 45,4 < X < 64,6 ] ???

P [ 45,4 < X < 64,6 ]

for X = 45,4

z₁ = ( X - μ₀ ) / σ

z₁ = 45,4 - 55 / 3,2

z₁ = - 9,6 / 3,2

z₁ = - 3

And fom z-table we find P [ X = 45,4 ] = 0,0013 or 0,13 %

z₂ = ( 64,6 - 55 )/ 3,2

z₂ = 3

And from z-table we find P [ X = 64,6 ] = 0,9987 or 99,87 %

Then

P [ 45,4 < X < 64,6 ] = 99,87 - 0,13 = 0,9974 or 99,74 %

Now if we look at the values:

μ₀ - 3*σ and μ₀ + 3*σ

we find 55 - 3*3,2 = 55 - 9,6 = 45,4 and 55 + 9,6 = 64,6

We know according to the empirical rule that values from μ₀ ± 3*σ will contains 99,7 % of all values

4 0

3 years ago

HELP ASAP!!!

Archy [21]

Answer:

x° = 50°

Step-by-step explanation:

x° + 130° = 180° (adjacent angles add up to 180°)

x° = 180° - 130°

x° = 50°

4 0

3 years ago

I don’t know what is marked correct (fake answers will be reported because it is frustrating )

juin [17]

I feel like it could be E? -7/4 is -1.75 , and that looks like E but i’m not sure

8 0

3 years ago

The distribution of actual weights of 8-oz chocolate bars produced by a certain machine is normal with mean 7.9 ounces and stand

fgiga [73]

Answer:

91.60% probability that the average weight of a bar in a simple random sample of three of these chocolate bars is between 7.76 and 8.09 ounces

Step-by-step explanation:

To solve this question, we need to understand 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 normally distributed random variable X, with mean $\mu$ and standard deviation $\sigma$ , the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$ .

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

In this problem, we have that:

$\mu = 7.9, \sigma = 0.16, n = 3, s = \frac{0.16}{\sqrt{3}} = 0.0924$

What is the probability that the average weight of a bar in a simple random sample of three of these chocolate bars is between 7.76 and 8.09 ounces?

This is the pvalue of Z when X = 8.09 subtracted by the pvalue of Z when X = 7.76. So

X = 8.09

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

By the Central Limit Theorem

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

$Z = \frac{8.09 - 7.9}{0.0924}$

$Z = 2.06$

$Z = 2.06$ has a pvalue of 0.9803

X = 7.76

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

$Z = \frac{7.76 - 7.9}{0.0924}$

$Z = -1.52$

$Z = -1.52$ has a pvalue of 0.0643

0.9803 - 0.0643 = 0.9160

91.60% probability that the average weight of a bar in a simple random sample of three of these chocolate bars is between 7.76 and 8.09 ounces

6 0

4 years ago

Fabio and Carlos play on a basketball team together. In the last game, Fabio had

Andreas93 [3]

Answer:

19 points

Step-by-step explanation:

Given that :

Fabio had 7 points less than 2 times as many points as Carlos

Let Fabio's point = f

Carlos point = c

Equation relating the number of points scored by both players.

Points scored by Fabio = 31

f = 2c - 7

Carlos point = c

31 = 2c - 7

31 + 7 = 2c

38 = 2c

c = 38/2

c = 19

Hence, Carlos's points is 19

8 0

3 years ago