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3 years ago

The cafeteria manager knows that about 300 students buy

Mathematics

1 answer:

Andrew [12]3 years ago

8 0

Answer:

I think its D

Step-by-step explanation:

300*20/100=60

It seems like a true prediction.

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A submarine was 38 feet below sea level it dove 45 more and then ascended 30 feet what is the submarines current elevation

bearhunter [10]

It is 53 feet below sea level.

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4 years ago

Read 2 more answers

Olivia uses the work below to determine 55% of 720.

Anna11 [10]

Answer:

396

Step-by-step explanation:

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3 years ago

The following data comparing wait times at two rides at Disney are listed below: Position Pirates Splash Mountain Sample Size 32

myrzilka [38]

Answer:

a) $(14.68 -18.77) - 2.39 \sqrt{\frac{11.87^2}{32}+\frac{16.79^2}{30}} =-12.968$

$(14.68 -18.77) + 2.39 \sqrt{\frac{11.87^2}{32}+\frac{16.79^2}{30}} =4.788$

b) $t=\frac{14.68-18.77}{\sqrt{\frac{11.87^2}{32}+\frac{16.79^2}{30}}}}=-1.10$

Step-by-step explanation:

Data given and notation

$\bar X_{A}=14.68$ represent the mean for Pirates

$\bar X_{B}=18.77$ represent the mean for Splash Mountain

$s_{A}=11.87$ represent the sample standard deviation for the sample Pirates

$s_{B}=16.79$ represent the sample standard deviation for the sample Slpash Mountain

$n_{A}=32$ sample size selected for Pirates

$n_{B}=30$ sample size selected for Splash Mountain

$\alpha=0.02$ represent the significance level for the hypothesis test.

t would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

Part a

The confidence interval would be given by:

$(\bar X_A -\bar X_B) \pm t_{\alpha/2} \sqrt{\frac{s^2_{A}}{n_{A}}+\frac{s^2_{B}}{n_{B}}}$

The degrees of freedom are given by:

$df = n_A +n_B -2 = 32+30-2 = 60$

Since we want 98% of confidence the significance level is $\alpha =1-0.98 =0.02$ and $\alpha/2 =0.01$ , we can find in the t distribution with df =60 a critical value that accumulates 0.01 of the area on each tail and we got:

$t_{\alpha/2}= 2.39$

And replacing we got for the confidence interval:

$(14.68 -18.77) - 2.39 \sqrt{\frac{11.87^2}{32}+\frac{16.79^2}{30}} =-12.968$

$(14.68 -18.77) + 2.39 \sqrt{\frac{11.87^2}{32}+\frac{16.79^2}{30}} =4.788$

Part b

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to check if the means are equal, the system of hypothesis would be:

Null hypothesis: $\mu_{A} = \mu_{B}$

Alternative hypothesis: $\mu_{A} \neq \mu_{B}$

the statistic is given by:

$t=\frac{\bar X_{A}-\bar X_{B}}{\sqrt{\frac{s^2_{A}}{n_{A}}+\frac{s^2_{B}}{n_{B}}}}$ (1)

t-test: "Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other".

Calculate the statistic

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

$t=\frac{14.68-18.77}{\sqrt{\frac{11.87^2}{32}+\frac{16.79^2}{30}}}}=-1.10$

6 0

3 years ago

Write an expression for the sequence of operations described below.

Lemur [1.5K]

This might look hard at first, but if you break it down into parts, it will be much easier. With that said, start with what you know. You see that the word problem says "the difference of y and 9", which means that you have to stubtract them. So, part of the equation is going to be y - 9. Now to look at the rest of the word problem. It says to divide by 3, so now you have to take what you have so far and divide that by 3. This means that you are going to have to divide the y - 9 by 3.

Your answer should be:
y - 9 / 3

***** Note: The slash means division. *************************************

8 0

3 years ago

Find the values of the six trigonometric functions for angle 0. write as fractions

nasty-shy [4]

Answer:

I accidently clicked answer and it won't let me quit

Step-by-step explanation:

I'm not even in high school yet D: sorry

7 0

3 years ago