Answer:
0.02275
Step-by-step explanation:
We have been given that the time needed to complete a final examination in a particular college course is normally distributed with a mean of 80 minutes and a standard deviation of 10 minutes. We are asked to find the probability of completing the exam in one hour or less.
We know that 1 hour equals 60 minutes. First of all, we will find the z-score corresponding to 60 minutes.

z = z-score,
x = Sample score,
= Mean,
= Standard deviation.



Now, we will use normal distribution table to find area under z-score of
as:


Therefore, the probability of completing the exam in one hour or less is 0.02275.
Answer:
OK with what
Step-by-step explanation:
OK with what
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
She has 64 cups
1 gallon is 16 cups