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3 years ago

Can I have help please on this math question

Mathematics

2 answers:

Sergeeva-Olga [200]3 years ago

8 0

I can’t see the image

GuDViN [60]3 years ago

3 0

Hi I want to help but I can’t see the image

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People in two sample groups were asked to identify their favorite kind of pizza. study the results and circle a generalization

Contact [7]

Answer:

Group B

Step-by-step explanation:

You can see even with the same total group b likes the most topppings

8 0

2 years ago

A simple random sample was taken of 44 water bottles from a bottling plant’s warehouse. The dissolvedoxygen content (in mg/L) wa

AleksAgata [21]

Answer:

a) $9.14-2.33\frac{2}{\sqrt{44}}=8.44$

$9.14+2.33\frac{2}{\sqrt{44}}=9.84$

b) The 98% confidence interval would be given by (8.44;9.84)

For this case we can conclude that we have 98% of confidence that the true mean for the oxygen content is between 8.44 and 9.84 mg/L

Step-by-step explanation:

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.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

$\bar X=9.14$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

$\sigma=2$ represent the population standard deviation

n=44 represent the sample size

Part a

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

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

In order to calculate the critical value $t_{\alpha/2}$ we need to find first the degrees of freedom, given by:

$df=n-1=18-1=17$

Since the Confidence is 0.98 or 98%, the value of $\alpha=0.01$ and $\alpha/2 =0.01$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-NORM.INV(0.01,0,1)".And we see that $z_{\alpha/2}=2.33$

Now we have everything in order to replace into formula (1):

$9.14-2.33\frac{2}{\sqrt{44}}=8.44$

$9.14+2.33\frac{2}{\sqrt{44}}=9.84$

Part b

The 98% confidence interval would be given by (8.44;9.84)

For this case we can conclude that we have 98% of confidence that the true mean for the oxygen content is between 8.44 and 9.84 mg/L

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4 years ago

At time t = 0 you have 100 grams of radioactive Chromium-48. Ten hours later you have 74 grams left. What is the half life of Ch

Snowcat [4.5K]

To calculate what is asked we use the formula for radioactive decay. It is expressed as follows:

An = Ao (e^(-kt))

We calculate as follows:

An = Ao (e^(-kt))
74 = 100 (e^(-k(10)))
k = 0.0301

1/2 = (e^(-0.0301t))
t = 23 hours

Hope this answers the question.

6 0

3 years ago

What is the approximate estimation for 29.942 + 13.433

Nana76 [90]

Answer:

the answer would be it is approximately 43.85

(did addition)

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3 years ago

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Solve for s. 1/2s=7/2 s=1/7 s=2/7 s=3 s=7

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