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3 years ago

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of all of the guest that will come to the picnic , you expect that 3/4 of them will eat desert. if 38 people came to the picnic,

about how many people will eat desert

1 answer:

Feliz [49]3 years ago

6 0

Answer:

1

Step-by-step explanation figure it out yourself di//ckkk/

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The perimeter of an equilateral triangle is 15x+30 units. Which expression can be used to show the side length of one side of th

lina2011 [118]

Correct Answer: Option D

An equilateral triangle is the one having all sides equal in length.

Let each side of the triangle is y units in length.

So, the perimeter of triangle will be = y + y + y = 3y units

This means,

3y = 15x + 30
3y = 3 (5x + 10)
y = 5x + 10

This means, each side of the equilateral triangle is 5x + 10 units in length.

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What is the approximate difference in the circumference of a circle with a radius of 4 ft and the circumference of a circle with

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Answer: 12.57 ft

Step-by-step explanation:

Circumference of circle with radius of 4ft.

= π * radius * 2

= 22/7 * 4 * 2

= 25.14 ft

Circumference of circle with radius of 6ft.

= 22/7 * 6 * 2

= 37.71 ft

Difference = 37.71 - 25.14

= 12.57 ft

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Order these fractions from least to greatest.<br> 3/8, 2/8 , 4/8

GarryVolchara [31]

The answer is :
2/8 < 3/8 < 4/8

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I need some help on how to do 8x/2=24. Whats the x?

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4 years ago

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Nonpregnant women have an average fasting blood glucose level of about 80 mg/100mL of blood. Researchers want to determine if pr

miss Akunina [59]

Answer:

a) The 90% confidence interval would be given by (71.689;78.311)

The 95% confidence interval would be given by (71.012;78.988)

b) $p_v =2*P(t_{24}$

If we compare the p value and the significance level assumed $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis. So we have a significant effect.

Step-by-step explanation:

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".

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".

$\bar X=75$ represent the sample mean

$\mu$ population mean (variable of interest)

$s=9.68$ represent the sample standard deviation

n=25 represent the sample size

Assuming the X follows a normal distribution

$X \sim N(\mu, \sigma=0.15$

The sample mean $\bar X$ is distributed on this way:

$\bar X \sim N(\mu, \frac{\sigma}{\sqrt{n}})$

Part a

The confidence interval on this case is given by:

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

We can find the degrees of freedom like this:

$df=n-1=25-1=24$

confidence 90%

The next step would be find the value of $\t_{\alpha/2}$ , $\alpha=1-0.90=0.1$ and $\alpha/2=0.05$

Using the t distribution with 24 df, excel or a calculator we see that:

$t_{\alpha/2}=1.71$

Since we have all the values we can replace:

$75 - 1.71\frac{9.68}{\sqrt{25}}=71.689$

$75 + 1.71\frac{9.68}{\sqrt{25}}=78.311$

So on this case the 90% confidence interval would be given by (71.689;78.311)

Confidence 95%

The next step would be find the value of $\t_{\alpha/2}$ , $\alpha=1-0.95=0.05$ and $\alpha/2=0.025$

Using the t distribution with 24 df, excel or a calculator we see that:

$t_{\alpha/2}=2.06$

Since we have all the values we can replace:

$75 - 2.06\frac{9.68}{\sqrt{25}}=71.012$

$75 + 2.06\frac{9.68}{\sqrt{25}}=78.988$

So on this case the 95% confidence interval would be given by (71.012;78.988)

Part b

Null hypothesis: $\mu = 80$

Alternative hypothesis: $\mu \neq 80$

Since we don't know the population deviation, is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:

$t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}$ (1)

t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

Calculate the statistic

We can replace in formula (1) the info given like this:

$t=\frac{75-80}{\frac{9.68}{\sqrt{25}}}=-2.583$

P-value

The degrees of freedom are 25-1=24

Since is a two tailed test the p value would given by:

$p_v =2*P(t_{24}$

Conclusion

If we compare the p value and the significance level assumed $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis. So we have a significant effect.

6 0

3 years ago