Answer:
Multiply by 10.
Step-by-step explanation:
When writing a number in scientific notation, if you move the decimal point to the left 3 places, then you must multiply by 10.
When you add it mentally you'd get 29
When you subtract it mentally you'd get 4.8
Well, let's say the numbers are "a" and "b"
so a * b = ab
ok... now, if we reduce "a" by 25%, that means the new size is just 75% of the old one, how much is 75% of a? well, (75/100) * a, or 0.75a
now let's reduce "b" by 50%, that means the new size is 50% or half, how much is 50% of b? well (50/100)*b, or 0.5b

now, the new size of "ab" is just 0.375ab... well, let's revert the decimal format by simply multiplying by 100
0.375 * 100, is 37.5%
the new size of "ab" is just 37.5% of the original "ab"
it decreased by 100 - 37.5 or 62.5%
Answer:

Step-by-step explanation:
See photo for steps.
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}](https://tex.z-dn.net/?f=%5Cbegin%7Bcenter%7D%0A%5Cbegin%7Btabular%7D%0A%7B%7Cc%7Cc%7C%7D%0AHours%20Spent%20Watching%20TV%20%26%20Grade%20on%20Test%20%28out%20of%20100%29%20%20%5C%5C%20%5B1ex%5D%0A4%20%26%2071%20%5C%5C%20%0A2%20%26%2081%20%5C%5C%20%0A4%20%26%2062%20%5C%5C%20%0A1%20%26%2086%20%5C%5C%20%0A3%20%26%2077%20%5C%5C%20%0A1%20%26%2093%20%5C%5C%20%0A2%20%26%2084%20%5C%5C%20%0A3%20%26%2080%20%5C%5C%20%0A2%20%26%2085%0A%5Cend%7Btabular%7D%0A%5Cend%7Bcenter%7D)
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}](https://tex.z-dn.net/?f=%5Cbegin%7Bcenter%7D%20%5Cbegin%7Btabular%7D%20%7B%7Cc%7Cc%7Cc%7Cc%7C%7D%20x%20%26%20y%20%26%20x%5E2%20%26%20xy%20%5C%5C%20%5B1ex%5D%204%20%26%2071%20%26%2016%20%26%20284%20%5C%5C%202%20%26%2081%20%26%204%20%26%20162%20%5C%5C%204%20%26%2062%20%26%2016%20%26%20248%20%5C%5C%201%20%26%2086%20%26%201%20%26%2086%20%5C%5C%203%20%26%2077%20%26%209%20%26%20231%20%5C%5C%201%20%26%2093%20%26%201%20%26%2093%20%5C%5C%202%20%26%2084%20%26%204%20%26%20168%20%5C%5C%203%20%26%2080%20%26%209%20%26%20240%20%5C%5C%202%20%26%2085%20%26%204%20%26%20170%20%5C%5C%20%5B1ex%5D%5CSigma%20x%3D22%20%26%20%5CSigma%20y%3D719%20%26%20%5CSigma%20x%5E2%3D64%20%26%20%5CSigma%20xy%3D1%2C682%20%5Cend%7Btabular%7D%20%5Cend%7Bcenter%7D)
Recall that the equation of the line of best fit of a regression analysis is given by

where:

and


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>