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AleksandrR [38]

3 years ago

11

Ana drew a map of the Panama Canal in the scale Ana used for the map 4 centimeters represents 20 kilometers what is the scale fa

ctor
A. 4/20

B. 4

C. 1/5

D. 5

1 answer:

Ganezh [65]3 years ago

5 0

Answer:

D

Step-by-step explanation:

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ASAP PLZZZZZZ NOW ! answer all questions

REY [17]

Answer:

68km

22miles

240km

Step-by-step explanation:

6 0

3 years ago

Read 2 more answers

Modern medical practice tells us not to encourage babies to become too fat. Is there a positive correlation between the weight x

Anna11 [10]

Answer:

a) Figure attached

b) $y=1.31 x +98.57$

c) The correlation coefficient would be r =0.47719

d) $y=1.31 x +98.57=1.31*21 + 98.57 =126.08$

Step-by-step explanation:

(a) Draw a scatter diagram for the data.

See the figure attached

(b) Find x, y, b, and the equation of the least-squares line. (Round your answers to three decimal places.) x =__ y =__ b =__ y =__ + __x

$m=\frac{S_{xy}}{S_{xx}}$

Where:

$S_{xy}=\sum_{i=1}^n x_i y_i -\frac{(\sum_{i=1}^n x_i)(\sum_{i=1}^n y_i)}{n}$

$S_{xx}=\sum_{i=1}^n x^2_i -\frac{(\sum_{i=1}^n x_i)^2}{n}$

With these we can find the sums:

$S_{xx}=\sum_{i=1}^n x^2_i -\frac{(\sum_{i=1}^n x_i)^2}{n}=6576-\frac{300^2}{14}=147.429$

$S_{xy}=\sum_{i=1}^n x_i y_i -\frac{(\sum_{i=1}^n x_i)(\sum_{i=1}^n y_i){n}}=38186-\frac{300*1773}{14}=193.143$

And the slope would be:

$m=\frac{193.143}{147.429}=1.31$

Nowe we can find the means for x and y like this:

$\bar x= \frac{\sum x_i}{n}=\frac{300}{14}=21.429$

$\bar y= \frac{\sum y_i}{n}=\frac{1773}{14}=126.643$

And we can find the intercept using this:

$b=\bar y -m \bar x=126.643-(1.31*21.429)=98.571$

So the line would be given by:

$y=1.31 x +98.57$

(c) Find the sample correlation coefficient r and the coefficient of determination r?2. (Round your answers to three decimal places.)

n=14 $\sum x = 300, \sum y = 1773, \sum xy=38186, \sum x^2 =6576, \sum y^2 =225649$

And in order to calculate the correlation coefficient we can use this formula:

$r=\frac{n(\sum xy)-(\sum x)(\sum y)}{\sqrt{[n\sum x^2 -(\sum x)^2][n\sum y^2 -(\sum y)^2]}}$

$r=\frac{14(38186)-(300)(1773)}{\sqrt{[14(6576) -(300)^2][14(225649) -(1773)^2]}}=0.9534$

So then the correlation coefficient would be r =0.47719

What percentage of variation in y is explained by the least-squares model? (Round your answer to one decimal place.)

The % of variation is given by the determination coefficient given by $r^2$ and on this case $0.47719^2 =0.2277$ , so then the % of variation explaines is 22.8%.

(d) If a female baby weighs 21 pounds at 1 year, what do you predict she will weigh at 30 years of age? (Round your answer to two decimal places.) ___ lb

So we can replace in the linear model like this:

$y=1.31 x +98.57=1.31*21 + 98.57 =126.08$

7 0

3 years ago

Is 7/12 bigger than 1/2

Varvara68 [4.7K]

Lets think of it this way:-

1/2 is one half

Whats half of 12? 6

Now, 7 is greater than 6, which means the fraction 7/12 is greater than 1/2

Answer: 7/12 is bigger

7 0

3 years ago

Read 2 more answers

A manufacturing machine has a 5% defect rate.

kodGreya [7K]

<h2>this is a PICTURE </h2>

<h3>i HOPE IT'S HELP </h3>

6 0

3 years ago

Who could help me please and thank you

kondor19780726 [428]

Answer:

"The expression represents a cubic polynomial with 3 terms. The constant term is -10, the leading degree is 3, and the leading coefficient is (-1/6)"

Step-by-step explanation:

We have the expression:

$-\frac{x^3}{6} - 10 + x$

First, what does that expression represents?

As al the powers of x are positive numbers, we can see that this is a polynomial, and the largest power is 3, so this is a polynomial of degree 3, also called a cubic polynomial.

How many terms are there?

The terms are the things separated by + or - symbols, is easy to see that there are 3 terms.

What is the constant term?

The constant term is the term where the variable, x, does not appear, here the constant term is: -10

What is the leading coefficient?

The leading coefficient is the coefficient that multiplies the term with the largest power of x, in this case, we can rewrite:

$-\frac{x^3}{6} -10 + x = (\frac{-1}{6})*x^3 - 10 + x$

the leading coefficient is:

(-1/6)

There is a part of the statement that I can't read, i suppose that there says:

"leading degree"

this is just the largest power of x that appears in the polynomial, in this case, is 3.

Then the complete statement is:

"The expression represents a cubic polynomial with 3 terms. The constant term is -10, the leading degree is 3, and the leading coefficient is (-1/6)"

5 0

3 years ago