Classify the following triangle by its side lengths:

It was -5 celsius in Copenhagen and -12 celsius in Oslo. Which city was colder?

BARSIC [14]

Answer:

Oslo

Step-by-step explanation: -12 is below -5. Therefore it is colder the further below on the temperature

4 0

3 years ago

Read 2 more answers

Some scientists believe alcoholism is linked to social isolation. One measure of social isolation is marital status. A study of

frez [133]

Answer:

1) H0: There is independence between the marital status and the diagnostic of alcoholic

H1: There is association between the marital status and the diagnostic of alcoholic

2) The statistic to check the hypothesis is given by:

$\sum_{i=1}^n \frac{(O_i -E_i)^2}{E_i}$

3) $\chi^2 = \frac{(21-33.143)^2}{33.143}+\frac{(37-41.429)^2}{41.429}+\frac{(58-41.429)^2}{41.429}+\frac{(59-46.857)^2}{46.857}+\frac{(63-58.571)^2}{58.571}+\frac{(42-58.571)^2}{58.571} =19.72$

4) $df=(rows-1)(cols-1)=(3-1)(2-1)=2$

And we can calculate the p value given by:

$p_v = P(\chi^2_{2} >19.72)=5.22x10^{-5}$

And we can find the p value using the following excel code:

"=1-CHISQ.DIST(19.72,2,TRUE)"

Since the p value is lower than the significance level so then we can reject the null hypothesis at 5% of significance, and we can conclude that we have association between the two variables analyzed.

Step-by-step explanation:

A chi-square goodness of fit test "determines if a sample data matches a population".

A chi-square test for independence "compares two variables in a contingency table to see if they are related. In a more general sense, it tests to see whether distributions of categorical variables differ from each another".

Assume the following dataset:

Diag. Alcoholic Undiagnosed Alcoholic Not alcoholic Total

Married 21 37 58 116

Not Married 59 63 42 164

Total 80 100 100 280

Part 1

We need to conduct a chi square test in order to check the following hypothesis:

H0: There is independence between the marital status and the diagnostic of alcoholic

H1: There is association between the marital status and the diagnostic of alcoholic

The level os significance assumed for this case is $\alpha=0.05$

Part 2

The statistic to check the hypothesis is given by:

$\sum_{i=1}^n \frac{(O_i -E_i)^2}{E_i}$

Part 3

The table given represent the observed values, we just need to calculate the expected values with the following formula $E_i = \frac{total col * total row}{grand total}$

And the calculations are given by:

$E_{1} =\frac{80*116}{280}=33.143$

$E_{2} =\frac{100*116}{280}=41.429$

$E_{3} =\frac{100*116}{280}=41.429$

$E_{4} =\frac{80*164}{280}=46.857$

$E_{5} =\frac{100*164}{280}=58.571$

$E_{6} =\frac{100*164}{280}=58.571$

And the expected values are given by:

Diag. Alcoholic Undiagnosed Alcoholic Not alcoholic Total

Married 33.143 41.429 41.429 116

Not Married 46.857 58.571 58.571 164

Total 80 100 100 280

And now we can calculate the statistic:

$\chi^2 = \frac{(21-33.143)^2}{33.143}+\frac{(37-41.429)^2}{41.429}+\frac{(58-41.429)^2}{41.429}+\frac{(59-46.857)^2}{46.857}+\frac{(63-58.571)^2}{58.571}+\frac{(42-58.571)^2}{58.571} =19.72$

Part 4

Now we can calculate the degrees of freedom for the statistic given by:

$df=(rows-1)(cols-1)=(3-1)(2-1)=2$

And we can calculate the p value given by:

$p_v = P(\chi^2_{2} >19.72)=5.22x10^{-5}$

And we can find the p value using the following excel code:

"=1-CHISQ.DIST(19.72,2,TRUE)"

Since the p value is lower than the significance level so then we can reject the null hypothesis at 5% of significance, and we can conclude that we have association between the two variables analyzed.

7 0

4 years ago

romeo ordered a bouquet of roses for his girlfriend. each rose cost $2.95. and the delivery charge was $8.50. if the total cost

LenaWriter [7]

Okay first you should subtract 8.50 from 61.60 because the delivery charge doesn't count. 61.60-8.50=53.1. now divide 53.1 by 2.95. 53.1÷2.95=18. Romeo ordered 18 roses for his girlfriend.

4 0

3 years ago

Read 2 more answers

Solve 13+b>34. Graph the solution. I give lots of points

enyata [817]

Question:

13 + b > 34

Step 1: Keep variable on one side, and subtract 13 on both sides.

b > 21

Step 2: Now that you have the value of b, create a number line that includes the number "21"

Step 3: Since it is not "or equal too" we will use an open dot, since we do not contain that point. Put dot over 21.

Step 4: The sign is ( > ) meaning greater than. Therefore all points greater than 21 is true. See graph.

8 0

3 years ago

How many window coverings are necessary to span 50 windows if each window covering is 15 windows long?

julia-pushkina [17]

The correct answer is: 
4.

Explanation: 
To find this answer, we divide the number of windows, 50, by the length (in windows covered) of each covering, 15:
 $\frac{50}{15} = 3 \frac{1}{3}$ .
This means that 3 coverings won't quite be long enough, so we will need 4.

4 0

3 years ago