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2 years ago

G

Mathematics

1 answer:

kvv77 [185]2 years ago

8 0

Answer:

Girls in Mr. Chang's class: 28 - 21 ; # girl students = # total students - # boy students ; 7 girl students.

Boys in Mr. Chang's class: 28 - 7 ; # boy students = # total students - girl students ; 21 boy students.

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A data set includes 108 body temperatures of healthy adult humans having a mean of 98.3degrees°F and a standard deviation of 0.6

mylen [45]

<h2>Answer with explanation:</h2>

The confidence interval for population mean is given by :-

$\overline{x}\pm z_{\alpha/2}\dfrac{\sigma}{\sqrt{n}}$

Given : Sample size : n=106

Sample mean : $\overline{x}=98.3^{\circ}\ F$

Standard deviation : $\sigma= 0.69^{\circ}F$

Significance level : $\alpha: 1-0.99=0.01$

Critical value : $z_{\alpha/2}=2.576$

Then , 99% confidence interval estimate of the mean body temperature of all healthy humans will be :-

$98.3\pm (2.576)\dfrac{0.69}{\sqrt{106}}\\\\\approx98.3\pm0.173=(98.3-0.173,\ 98.3+0.173)=(98.127,\ 98.473)$

Since 98.6 is higher than the upper limit of the confidence interval (98.473), then this suggest that the mean body temperature could be lower then 98.6 degrees.

The best estimate of population mean is always the sample mean. $\mu=\overline{x}=98.3^{\circ}\ F$

7 0

2 years ago

A store is selling a mixture of apple granola and blueberry granola for $6.99 per pound. Blueberry granola costs $8.99 per pound

Alik [6]

Answer:the number of pounds of blueberry granola that she should put in the mixture is 10 pounds.

the number of pounds of apple granola that she should put in the mixture is 20 pounds

Step-by-step explanation:

Let x represent the number of pounds of blueberry granola that she should put in the mixture.

Let y represent the number of pounds of apple granola that she should put in the mixture.

She wants to make a 30 pounds mixture. This means that

x + y = 30

A store is selling a mixture of apple granola and blueberry granola for $6.99 per pound. This means that the cost of the 30 pound mixture would be

30 × 6.99 = $209.7

Blueberry granola costs $8.99 per pound and apple granola costs $5.99. This means that

8.99x + 5.99y = 209.7 - - - - - - - - - -1

Substituting x = 30 - y into equation 1, it becomes

8.99(30 - y) + 5.99y = 209.7

269.7 - 8.99y + 5.99y = 209.7

- 8.99y + 5.99y = 209.7 - 269.7

- 3y = - 60

y = - 60/ -3

y = 20

Substituting y = 20 into x = 30 - y, it becomes

x = 30 - 20 = 10 pounds

7 0

2 years ago

Help with this slope

gladu [14]

Answer:

20,100 I think

Step-by-step explanation:

8 0

2 years ago

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#40 please! Thank you.

lisov135 [29]

Well he and the cart together weigh: 210+95=305.
The weight left for boxes is: 4,000-305=3,695.
Total weight of boxes is: 50·275=13,750.
Divide the weight of boxes by how much is left for the elevator: 13,750/3,695=3.72
Since 3.72 is more than 3 he would have to make 4 trips to safely do so :)

5 0

2 years ago

2+2+2+2+2+2+(2x9x9x9x9xx9x9)=?

Luden [163]

Answer:

50000000

Step-by-step explanation:

Do it yourself

6 0

2 years ago

Read 2 more answers