Find the equation of the line containing the points (-3, -10) and (12, 0)

At the Foremost State Bank the average savings account balance in 2012 was $1900. A random sample of 45 savings account balanes

lakkis [162]

Answer:

The calculated |t| = |-26.517|=26.517 > 2.326 at 0.01 level of significance

Null hypothesis is rejected at 0.01 level of significance

There is difference between mean savings account balance in 2013 is different from the mean savings account balance in 2012

Step-by-step explanation:

Step(i):-

Mean of the Population = 1900

Given random sample size 'n' = 45

Mean of the sample x⁻ = 1000

Standard deviation of the sample = 225

Null Hypothesis:-

There is no difference between mean savings account balance in 2013 is different from the mean savings account balance in 2012.

Alternative Hypothesis :-

There is difference between mean savings account balance in 2013 is different from the mean savings account balance in 2012

Step(ii):-

Test statistic

$t = \frac{x^{-}-mean }{\frac{S.D}{\sqrt{n} } }$

$t = \frac{1000-1900 }{\frac{225}{\sqrt{45} } }$

t = -900 /33.54 = -26.517

|t| = |-26.517|=26.517

Degrees of freedom

γ = n-1 = 45-1 =44

t₍₀.₀₁ , ₄₄₎ = 2.326

The calculated |t| = |-26.517|=26.517 > 2.326 at 0.01 level of significance

Null hypothesis is rejected at 0.01 level of significance

There is difference between mean savings account balance in 2013 is different from the mean savings account balance in 2012

4 0

3 years ago

What is a fraction of a fraction

Vikentia [17]

<h3> - - - - - - - - - - - - - ~Hello There!~ - - - - - - - - - - - - - </h3>

➷ When it comes to dividing fractions, there is a rule you must now.

It's called Keep Flip Change.

I'll give you an example:

$\frac{2}{7} / \frac{4}{6}$

Keep the first fraction exactly as it is

Flip the second fraction upside down (switch the numerator and denominator around)

Change the sign to a multiplication.

This is how it should look:

$\frac{2}{7} *\frac{6}{4}$

Now you just multiply them as you normally would to get an answer of:

$\frac{12}{28}$

➶Hope This Helps You!

➶Good Luck :)

➶Have A Great Day ^-^

↬ Hannah ♡

6 0

3 years ago

HELP Find the least common denominator (LCD) of eight ninths and 1 and one third.

Ludmilka [50]

9 is the LCD of 8/9 and 1/3. please mark thanks!

3 0

3 years ago

Read 2 more answers

83 random samples were selected from a normally distributed population and were found to have a mean of 32.1 and a standard devi

arlik [135]

Answer:

$\frac{(82)(2.4)^2}{104.139} \leq \sigma^2 \leq \frac{(82)(2.4)^2}{62.132}$

$4.525 \leq \sigma^2 \leq 7.602$

Now we just take square root on both sides of the interval and we got:

$2.127 \leq \sigma \leq 2.757$

Step-by-step explanation:

Information given

$\bar X=32.1$ represent the sample mean

$\mu$ population mean (variable of interest)

s=2.4 represent the sample standard deviation

n=83 represent the sample size

Confidence interval

The confidence interval for the population variance is given by the following formula:

$\frac{(n-1)s^2}{\chi^2_{\alpha/2}} \leq \sigma^2 \leq \frac{(n-1)s^2}{\chi^2_{1-\alpha/2}}$

The degrees of freedom given by:

$df=n-1=8-1=7$

The confidence level is 0.90 or 90%, the value of $\alpha=0.1$ and $\alpha/2 =0.05$ , and we can use excel, a calculator or a table to find the critical values.

The excel commands would be: "=CHISQ.INV(0.05,82)" "=CHISQ.INV(0.95,82)". so for this case the critical values are:

$\chi^2_{\alpha/2}=104.139$

$\chi^2_{1- \alpha/2}=62.132$

The confidence interval is given by:

$\frac{(82)(2.4)^2}{104.139} \leq \sigma^2 \leq \frac{(82)(2.4)^2}{62.132}$

$4.525 \leq \sigma^2 \leq 7.602$

Now we just take square root on both sides of the interval and we got:

$2.127 \leq \sigma \leq 2.757$

5 0

3 years ago

Summer clothes are on sale starting September 1st. A swimsuit is on sale for 40% off the regular selling price of $55.00. What i

o-na [289]

55 / 100 = 0.55 which is 1%

0.55 x 40 = 22 which is 40%

55 - 22 = 33

The answer is $33

5 0

3 years ago