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Zielflug [23.3K]
4 years ago
5

The ratio of boys to girls is 7:12. If there are 76 children how many are girls?

Mathematics
2 answers:
LuckyWell [14K]4 years ago
5 0

Answer:

Step-by-step explanation:

I need help

Lera25 [3.4K]4 years ago
4 0

Answer:

28 girls

Step-by-step explanation:

Given girls : boys ===> 7 : 12

i.e.

fraction all children who are girls = 7 / (7 + 12) = 7 / 19

fraction all children who are boys = 12 / (7 + 12) = 12 / 19

given that there are 76 children

number of girls = fraction of all children who are girls x total number of children

= 7/19   x   76

= 28 girls

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You work in the HR department at a large franchise. you want to test whether you have set your employee monthly allowances corre
ra1l [238]

Answer:

1) Null hypothesis:\mu \leq 500  

Alternative hypothesis:\mu > 500  

z=\frac{640-500}{\frac{150}{\sqrt{40}}}=5.90  

For this case since we are conducting a right tailed test we need to find a critical value in the normal standard distribution who accumulates 0.01 of the area in the right and we got:

z_{crit}= 2.33

For this case we see that the calculated value is higher than the critical value

Since the calculated value is higher than the critical value we have enugh evidence to reject the null hypothesis at 1% of significance level

2) Since is a right tailed test the p value would be:  

p_v =P(z>5.90)=1.82x10^{-9}  

If we compare the p value and the significance level given \alpha=0.01 we see that p_v so we can conclude that we have enough evidence to reject the null hypothesis, same conclusion for part 1

Step-by-step explanation:

Part 1

Data given

\bar X=640 represent the sample mean

\sigma=150 represent the population standard deviation

n=40 sample size  

\mu_o =500 represent the value that we want to test  

\alpha=0.01 represent the significance level for the hypothesis test.  

z would represent the statistic (variable of interest)  

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

Step1:State the null and alternative hypotheses.  

We need to conduct a hypothesis in order to check if the true mean is higher than 500, the system of hypothesis would be:  

Null hypothesis:\mu \leq 500  

Alternative hypothesis:\mu > 500  

Step 2: Calculate the statistic

z=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}} (1)  

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

z=\frac{640-500}{\frac{150}{\sqrt{40}}}=5.90  

Step 3: Calculate the critical value

For this case since we are conducting a right tailed test we need to find a critical value in the normal standard distribution who accumulates 0.01 of the area in the right and we got:

z_{crit}= 2.33

Step 4: Compare the statistic with the critical value

For this case we see that the calculated value is higher than the critical value

Step 5: Decision

Since the calculated value is higher than the critical value we have enugh evidence to reject the null hypothesis at 1% of significance level

Part 2

P-value  

Since is a right tailed test the p value would be:  

p_v =P(z>5.90)=1.82x10^{-9}  

If we compare the p value and the significance level given \alpha=0.01 we see that p_v so we can conclude that we have enough evidence to reject the null hypothesis, same conclusion for part 1

7 0
3 years ago
The author received a total of $195,000 for the book sales. How many hardcover books were sold? Type in numbers only.
g100num [7]

Answer:

Total 390 hardcover books were sold

Step-by-step explanation:

Complete question

The author received a total of $195,000 for the book sales. How many hardcover books were sold if the cost of one hardcover book is  $500. Type in numbers only.

Solution

Given-

Total value of sale of hard cover = $195,000

Cost of one hardcover book = $500

Number of books sold = Total value of sale of hard cover/Cost of one hardcover book

Number of books sold =   $195,000/$500

Number of books sold = 390

Total 390 hardcover books were sold.

3 0
3 years ago
Worth 21 points and giving brianliest!!!! Please help ASAP
Schach [20]

Answer:

Step 3

Step-by-step explanation:

This is the right one because you are adding two thing in step two which lead to step 3

5 0
3 years ago
Beneze recipe for granola bars close for 3 1/2 cups of oatmeal he only has 16 cup scoop how many scoops of oatmeal he need for t
LUCKY_DIMON [66]
16/3 1/2= 7/32. so you would measure 7/32 on the 16 cup scoop
7 0
3 years ago
HELP
kati45 [8]

Slope: 1/5

Y-intercept: 0

Equation: Y= 5x

5 0
3 years ago
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