Answer:
C
Step-by-step explanation:
The line of best fit is a linear function that is closest to all the points and shows the trend in the data. Since the data is going up ultimately, the slope of the line will be positive. Only B and C are options.
To find the best fit, draw a line through the center of the most points. This line will have as its y-intercept a value around 12 and a gentle slope. This means the answer choice is C.
Since y is .95 and x is 1 it is a unit rate which is the constant of proportionality.
Correct me if I am wrong.
Average (mean) = (sum of all the data) / (# of data)
sum of all the data = (average)(# of data)
Thus for 100 students with an average of 93,
sum of all data = (93)(100) = 9300
and for 300 students with an average of 75,
sum of all data = (75)(300) = 22500
Therefore you would expect the overall average to be
(9300 + 22500) / (100 + 300) = 79.5 %
Now if there are x # of advanced students and y # of regular students, then
x + y = 90 (total # of students) and 93x + 75y = 87(x + y) (overall average)
The second equation can be simplified to x - 2y = 0
Subtracting the two equations yields
x = 60 and y = 90
Therefore you would need 60 advanced and 30 regular students.
