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3 years ago

How many cubes with side lengths of cm does it take to fill the prism?

Mathematics

1 answer:

Sophie [7]3 years ago

5 0

The answer is Stan twiceushisnsskkemr

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Number 6: Which is closer to 0.0009999? 0, 1/2, or 1?

aliya0001 [1]

0.
1/2 is equivalent to 0.5
1 is equivalent to 1.0

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3 years ago

Devin has 8 lengths of ribbon 1 meter long each. she cuts the ribbon lengths into fourths. how many fourths will she have after

Nostrana [21]

2/8 is the answer

hope this helps you

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3 years ago

Read 2 more answers

An experiment was conducted to observe the effect of an increase in temperature on the potency of an antibiotic. Three 1-ounce p

ludmilkaskok [199]

Answer:

a) $y=-0.317 x +46.02$

b) Figure attached

c) $S^2=\hat \sigma^2=MSE=\frac{190.33}{10}=19.03$

Step-by-step explanation:

We assume that th data is this one:

x: 30, 30, 30, 50, 50, 50, 70,70, 70,90,90,90

y: 38, 43, 29, 32, 26, 33, 19, 27, 23, 14, 19, 21.

a) Find the least-squares line appropriate for this data.

For this case we need to calculate the slope with the following formula:

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

Where:

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

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

So we can find the sums like this:

$\sum_{i=1}^n x_i = 30+30+30+50+50+50+70+70+70+90+90+90=720$

$\sum_{i=1}^n y_i =38+43+29+32+26+33+19+27+23+14+19+21=324$

$\sum_{i=1}^n x^2_i =30^2+30^2+30^2+50^2+50^2+50^2+70^2+70^2+70^2+90^2+90^2+90^2=49200$

$\sum_{i=1}^n y^2_i =38^2+43^2+29^2+32^2+26^2+33^2+19^2+27^2+23^2+14^2+19^2+21^2=9540$

$\sum_{i=1}^n x_i y_i =30*38+30*43+30*29+50*32+50*26+50*33+70*19+70*27+70*23+90*14+90*19+90*21=17540$

With these we can find the sums:

$S_{xx}=\sum_{i=1}^n x^2_i -\frac{(\sum_{i=1}^n x_i)^2}{n}=49200-\frac{720^2}{12}=6000$

$S_{xy}=\sum_{i=1}^n x_i y_i -\frac{(\sum_{i=1}^n x_i)(\sum_{i=1}^n y_i)}=17540-\frac{720*324}{12}{12}=-1900$

And the slope would be:

$m=-\frac{1900}{6000}=-0.317$

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

$\bar x= \frac{\sum x_i}{n}=\frac{720}{12}=60$

$\bar y= \frac{\sum y_i}{n}=\frac{324}{12}=27$

And we can find the intercept using this:

$b=\bar y -m \bar x=27-(-0.317*60)=46.02$

So the line would be given by:

$y=-0.317 x +46.02$

b) Plot the points and graph the line as a check on your calculations.

For this case we can use excel and we got the figure attached as the result.

c) Calculate S^2

In oder to calculate S^2 we need to calculate the MSE, or the mean square error. And is given by this formula:

$MSE=\frac{SSE}{df_{E}}$

The degred of freedom for the error are given by:

$df_{E}=n-2=12-2=10$

We can calculate:

$S_{y}=\sum_{i=1}^n y^2_i -\frac{(\sum_{i=1}^n y_i)^2}{n}=9540-\frac{324^2}{12}=792$

And now we can calculate the sum of squares for the regression given by:

$SSR=\frac{S^2_{xy}}{S_{xx}}=\frac{(-1900)^2}{6000}=601.67$

We have that SST= SSR+SSE, and then SSE=SST-SSR= 792-601.67=190.33[/tex]

So then :

$S^2=\hat \sigma^2=MSE=\frac{190.33}{10}=19.03$

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3 years ago

I need help with 4th grade math please show the problem and strategies thank you so much

irakobra [83]

70 palm trees are on that street

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3 years ago

4 days I have 140 copies of a book, 9 days I only have 50 left. Write an equation where c(t)=my+b where c is number of copies st

alexandr402 [8]

Answer:

$c(t)=-18t+212$ .

Step-by-step explanation:

We have been given that 4 days I have 140 copies of a book, 9 days I only have 50 left. We are asked to write an equation $c(t)=my+b$ , where c is number of copies still on hand and t days being available.

We have two points on line (4,140) and (9,50). Now, we will use these points to find slope as:

$m=\frac{140-50}{4-9}$

$m=\frac{90}{-5}$

$m=-18$

Now, we will use point-slope form of equation $y-y_1=m(x-x_1)$ and substitute $m=-18$ and coordinates of point (9,50) as:

$y-50=-18(x-9)$

$y-50=-18x+162$

$y-50+50=-18x+162+50$

$y=-18x+212$

Therefore, our required equation would be $c(t)=-18t+212$ .

5 0

4 years ago