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3 years ago

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A random sample of size 21 was taken from a normal population. the sample average was 9.87 and the sample sd was 1.17. at the si

gnificance level of 10%, what test should you use for testing whether the population mean equals 9.7?

1 answer:

Olin [163]3 years ago

6 0

You should be using a hypothesis test - One sample T test.

The answer is given below.

Test of mu = 9.7 vs not = 9.7

The assumed standard deviation = 1.17

N Mean SE Mean 90% CI Z P

21 9.87000 0.25531 (9.45004, 10.28996) 0.67 0.506

since P value is greater than 0.05 we accept the null hypothesis that the population mean equals 9.7

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¿Cuanto es el 15% de 9,000?

bazaltina [42]

Answer:

10% = 900

5% = 450

15% = 1,350

Please brainliest

4 0

3 years ago

How do u do this problem: W/6+5/8=-1 3/8 <br> I got this answer: -1 53/64

Kobotan [32]

We have question
$\frac{W}{6}+ \frac{5}{8} =-1 \frac{3}{8}$
$\frac{W}{6} + \frac{5}{8} =- \frac{11}{8}$ <span> /*8 (multiply both sides by 8)</span>
$\frac{W8}{6} + \frac{5}{1} =- \frac{11}{1}$ /*6 (multiply both sides by 6)
$8W+5*6=-11*6$ /-30 both sides
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6 0

3 years ago

Read 2 more answers

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

Miranda found out that there are 20 drops in 11 mL of medicine. She measured 15 drops of medicine into a measuring cup. How many

andreyandreev [35.5K]

Answer: Her measuring cup has 8.25 mL of medicine.

Step-by-step explanation:

As per given,

In 11 mL of medicine, there are 20 drops.

That means quantity in 1 drop = $\dfrac{11}{20}$ mL

Now , the quantity in 15 drops = 15 x quantity in 1 drop

= $15\times\dfrac{11}{20}$

$=\dfrac{33}{4}$

= 8.25 mL

Hence, her measuring cup has 8.25 mL of medicine.

6 0

3 years ago

Order the fraction and decimals from least to greatest.<br> 0.78, 0.5, 3/5

ExtremeBDS [4]

Answer:

0.5, 3/5, 0.78

Step-by-step explanation:

3 0

3 years ago

Read 2 more answers