Step-by-step explanation:
We can set up a proportion since we know the ratio between the # of purple marbles and the # of green marbles.
A ratio is a way to compare two different values: for every 8 purple marbles there are 5 green marbles
<h2>

</h2><h2 /><h2>when we cross multiply, we get 5p = 240 </h2><h2>we divide both sides by 5 to isolate the variable </h2><h2 /><h3><u>There are 48 purple marbles </u></h3>
A) The attachment shows the equation of the best-fit line. It is approximately
.. test average = 89.7 -2.93*(hours playing games)
b) The slope indicates the expected drop in test score for each hour spent playing games
c) The y-intercept is the expected test score if no hours are spent playing games.
d) The correlation coefficient is -0.92, a significant negative correlation. One might expect that hours spent playing games indicates a lack of interest in school subjects or studying, hence a likelihood that test scores will be lower.
e) The equation predicts a test score of about 75 for someone who spends 5 hours a week playing video games.
Y = -3x + c
Using (1,-5):
-5 = -3(1) + c
c = -5 + 3(1) = -2
Therefore:
y = -3x - 2

=
1/3 ( because the limit as x approaches 0 of t/sin t = 1 ).