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3 years ago

15

Brian has reduced his cholesterol level by 20% by following a strict diet and regular exercise. If his original level was 220, w

hat is his cholesterol level now?

1 answer:

Andreas93 [3]3 years ago

6 0

His level is at 176 because if you subtract %20 of 220 (44) you get 176

You might be interested in

What is -2(4g-3)=30 I can't figure it out so I need so help

Sunny_sXe [5.5K]

Answer:-3

Step-by-step explanation:do the distributive property. So let's simplify it more: -8g+6=30. Minus the positive 6 to make it a zero then minus the 30 to make it a 24. -8g=24 is what's left. Divide both sides by negative 8: g= -3

4 0

3 years ago

4. You want to know if there's an association between college students' spring break destinations and what year they're in. You

Pachacha [2.7K]

Answer:

$\chi^2 =27.356$

$p_v = P(\chi^2_{9} >27.356)=0.00122$

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

"=1-CHISQ.DIST(27.356,9,TRUE)"

Since the p value is lower than the significance level assumed 0.05 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:

Amusement Parks Mexico Home Other Total

Freshman 23 21 43 21 108

Sophomore 34 23 14 26 97

Junior 25 30 23 26 104

Senior 27 33 17 19 96

Total 109 107 97 92 405

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

H0: There is independence between the two random variables

H1: There is dependence between the two variables

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

The statistic to check the hypothesis is given by:

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

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:

$E_{1} =\frac{109*108}{405}=29.07$

$E_{2} =\frac{107*108}{405}=28.53$

$E_{3} =\frac{97*108}{405}=25.87$

$E_{4} =\frac{92*108}{405}=24.53$

$E_{5} =\frac{109*97}{405}=26.11$

$E_{6} =\frac{107*97}{405}=25.63$

$E_{7} =\frac{97*97}{405}=23.23$

$E_{8} =\frac{92*97}{405}=22.03$

$E_{9} =\frac{109*104}{405}=27.99$

$E_{10} =\frac{107*104}{405}=27.48$

$E_{11} =\frac{97*104}{405}=24.91$

$E_{12} =\frac{92*104}{405}=23.62$

$E_{13} =\frac{109*96}{405}=25.84$

$E_{14} =\frac{107*96}{405}=25.36$

$E_{15} =\frac{97*96}{405}=22.99$

$E_{16} =\frac{92*96}{405}=21.81$

And the expected values are given by:

Amusement Parks Mexico Home Other Total

Freshman 29.07 28.53 25.87 24.53 108

Sophomore 26.11 25.63 23.23 22.03 97

Junior 27.99 27.48 24.91 23.62 104

Senior 25.84 25.36 22.99 21.81 96

Total 109 107 97 92 405

And now we can calculate the statistic:

$\chi^2 =27.356$

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

$df=(rows-1)(cols-1)=(4-1)(4-1)=9$

And we can calculate the p value given by:

$p_v = P(\chi^2_{9} >27.356)=0.00122$

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

"=1-CHISQ.DIST(27.356,9,TRUE)"

Since the p value is lower than the significance level assumed 0.05 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

3 years ago

123 Savings and Loan charges a monthly fee of $8 on checking accounts and an overdraft protection fee of $33. Neela's check regi

Stells [14]

Based on the calculation below, the balance on Neela's statement is $153.

<h3>How do we calculate the balance on a bank statement?</h3>

The balance on Neela's statement can be calculated using the following formula:

Balance on statement = Actual amount in the account - Monthly fee - Overdraft protection fee - Check written + Amount transferred ............ (1)

Substituting all the relevant values into equation (1), we have:

Balance on statement = $256 - $8 - $33 - $312 + $250

Balance on statement = $153

Learn more about bank statement balance here: brainly.com/question/13837329.

#SPJ1

8 0

2 years ago

It took 7.2 minutes to upload 8 digital photographs from your computer to a website. At this rate, how long will it take to uplo

kenny6666 [7]

If it take some x minutes to upload some y digital photographs, it means it has an average of: x/y minutes to upload a single digital photograph. Then, to upload z photographs, you just multiply x/y by z.

Spoilers for answer:
If it take 7.2 minutes to upload 8 digital photographs, it means it has an average of: 7.2/8 = 0.9 minutes to upload a single digital photograph. This means that, by this rate, it will take 20 * 0.9 = 18 minutes to upload 20 photographs to the website.

5 0

3 years ago

Find the quotient simplify your answers a+3 over a divided by 8 over a

mihalych1998 [28]

ANSWER

$\frac{a + 3}{8}$

EXPLANATION

We want to simplify

$\frac{a + 3}{a} \div \frac{8}{a}$

We multiply the first fraction by the reciprocal of the second fraction to obtain,

$\frac{a + 3}{a} \times \frac{a}{8}$

We cancel the common factors to get,

$\frac{a + 3}{1} \times \frac{1}{8}$

This gives us,

$\frac{a + 3}{8}$

4 0

3 years ago