A shopper bought the following items at the farmers market:

I surveyed students in my Math II classes to see how many hours of television they watched the night before our big test on tria

Oduvanchick [21]

Given the table below representing the number of hours of television nine Math II class students watched the night before a big test on triangles along with the grades they each earned on that test.

$\begin{center}
\begin{tabular}
{|c|c|}
Hours Spent Watching TV & Grade on Test (out of 100) \\ [1ex]
4 & 71 \\ 
2 & 81 \\ 
4 & 62 \\ 
1 & 86 \\ 
3 & 77 \\ 
1 & 93 \\ 
2 & 84 \\ 
3 & 80 \\ 
2 & 85
\end{tabular}
\end{center}$

Let the number the number of hours of television each of the students watched the night before the test be x while the grades they each earned on that test be y.

We use the following table to find the equation of the line of best fit of the regression analysis of the data.

$\begin{center} \begin{tabular} {|c|c|c|c|} x & y & x^2 & xy \\ [1ex] 4 & 71 & 16 & 284 \\ 2 & 81 & 4 & 162 \\ 4 & 62 & 16 & 248 \\ 1 & 86 & 1 & 86 \\ 3 & 77 & 9 & 231 \\ 1 & 93 & 1 & 93 \\ 2 & 84 & 4 & 168 \\ 3 & 80 & 9 & 240 \\ 2 & 85 & 4 & 170 \\ [1ex]\Sigma x=22 & \Sigma y=719 & \Sigma x^2=64 & \Sigma xy=1,682 \end{tabular} \end{center}$

Recall that the equation of the line of best fit of a regression analysis is given by
$y=a+bx$
where:
$a= \frac{(\Sigma y)(\Sigma x^2)-(\Sigma x)(\Sigma xy)}{n(\Sigma x^2)-(\Sigma x)^2}$
and
$b= \frac{n(\Sigma xy)-(\Sigma x)(\Sigma y)}{n(\Sigma x^2)-(\Sigma x)^2}$

$y=\frac{(719)(64)-(22)(1,682)}{9(64)-(22)^2}+\frac{9(1,682)-(22)(719)}{9(64)-(22)^2}x \\ \\ = \frac{46,016-37,004}{576-484} + \frac{15,138-15,818}{576-484} x \\ \\ = \frac{9,012}{92} + \frac{-680}{92} x \\ \\ =97.95-7.391x$

Thus, the equation of the line of best fit is given by y = 97.95 - 7.391x

<span>A student that watched 1.5 hours of TV will have a score given by
y = 97.95 - 7.391(1.5) = 97.95 - 11.0865 = 86.8635

Therefore, </span><span>a student’s score if he/she watched 1.5 hours of TV to the nearest whole number is 87.</span>

6 0

3 years ago

Does anyone know this lol

koban [17]

Answer:

62.5

Step-by-step explanation:

P = (6.50f) - 100

All you have to do is plug in 25 for f in the equation and solve for P.

P = (6.50*25) - 100

P = 162.5 - 100

P = 62.5

4 0

3 years ago

Two counters are selected at random from a bag containing 5 red counters and 3 blue counters.

azamat

Answer:

1.4

Step-by-step explanation:

Probability of selecting a red counter :

Number of red counter / total number of counters

5 / (5 + 3) = 5 /8 = 0.625

Probability of selecting a blue counter = 0.375

Let number of red counters :

0, 1 or 2

0 red counters :

Expected value = x * p(x)

0 + (0.625*1) + (0.390625 * 2)

0 + 0.625 + 0.78125 = 1.40625

Expected number of red counters = 1.4

6 0

3 years ago

Can somebody help me with this please.

Ksju [112]

I don't know what number 1 and number 2 mean,

3：11

4

5：-3

6：-8

You can find the answer below. Among the questions I answered correctly, I hope to adopt it at the end. Thank you. Have a nice day.

4 0

3 years ago

13. Find the surface area of each figure to the nearest tenth. Show your work.

stiv31 [10]

A. The figure is a triangular pyramid. You can findits surface area by adding up the area of the three faces of the triangle and the area of the base. A derived formula also is used where the SA is equal to 12 times the perimeter of base times the slant height, added to that is the area of the base. The area of the square base is s^2. Its perimeter is 4s.

SA of Pyramid = 12*P*l + s^2
SA of Pyramid = 12*4s*l + 16^2
SA of Pyramid = 12*4(16)*(17) + (16)^2
SA of Pyramid = 11,008 square inches

b.) The formula for the SA of a cone is:

SA of cone = πr[r+√(h^2+r^2)]
SA of cone = π(3)[(3+√(8^2+3^2)]
SA of cone = 108.8 square inches

7 0

3 years ago

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