Answer:
The diameter is any straight line that passes through the center of the circle, which endpoints can lie on. The radius is half the diameter. They help us find the circumference of a circle
This question is incomplete, the complete question is;
Suppose John is a high school statistics teacher who believes that watching many hours of TV leads to lower test scores. Immediately after giving the most recent test, he surveyed each of the 24 students in his class and asked them how many hours of TV they watched that week. He then matched each student's test grade with his or her survey response. After compiling the data, he used hours of TV watched to predict each student's test score. He found the least-squares regression line to be y" = -1.5x + 85.
He also calculated that the value of r, the correlation, was -0.61.
what is the correct value of the coefficient of determination R² and give a correct interpretation of its meaning
Answer:
Interpretation of coefficient of determination R² = 0.3721
R² = 0.3721, meaning 37.21% of the total variation in test scores can be explained by the least square regression line
Step-by-step explanation:
Given the data in the question;
the least square regression line is;
y" = -1.5x + 85
the correlation coefficient r = -0.61
Now, the coefficient of determination R² is square of correlation coefficient r
R² = -61²
R² = 0.3721
Answer:
Step-by-step explanation:
Given the Total revenue R(x) = 2x
Cost C(x) = 0.01x²+0.3x+30 where;
x = 30 and dx/dt = 9units per day.
Rate of change of revenue dR/dt = dR/dx • dx/dt
dR/dt = 2dx/dt
dR/dt = 2(9) = $18
Rate of change of revenue with respect to time is 18dollars/day.
Rate of change of cost dC/dt = dC/dx • dx/dt
dC/dt = (0.02x+0.3)dx/dt
dC/dt at x = 30 and dx/dt = 9 will give;
dC/dt = {0.02(30)+0.3}×9
dC/dt = (0.6+0.3) × 9
dC/dt = 0.9×9
dC/dt = $8.1
Rate of change of cost with respect to time is 8.1dollars/day
Profit = Revenue - Cost
Profit = 18-8.1
Daily Profit = $9.9
