Answer:
dA/dt = k1(M-A) - k2(A)
Step-by-step explanation:
If M denote the total amount of the subject and A is the amount memorized, the amount that is left to be memorized is (M-A)
Then, we can write the sentence "the rate at which a subject is memorized is assumed to be proportional to the amount that is left to be memorized" as:
Rate Memorized = k1(M-A)
Where k1 is the constant of proportionality for the rate at which material is memorized.
At the same way, we can write the sentence: "the rate at which material is forgotten is proportional to the amount memorized" as:
Rate forgotten = k2(A)
Where k2 is the constant of proportionality for the rate at which material is forgotten.
Finally, the differential equation for the amount A(t) is equal to:
dA/dt = Rate Memorized - Rate Forgotten
dA/dt = k1(M-A) - k2(A)
Given Information:
Mean time to finish 400 meter dash = μ = 65 seconds
Standard deviation to finish 400 meter dash = σ = 2.5 seconds
Confidence level = 95%
Required Information:
95% confidence interval = ?
Answer:

Step-by-step explanation:
In the normal distribution, the empirical rule states approximately 68% of all the data lie within 1 standard deviation from the mean, approximately 95% of all the data lie within 2 standard deviations from the mean and approximately 99.7% of all the data lie within 3 standard deviations from the mean.
The confidence interval for 95% confidence limit is given by

Since approximately 95% of all the data lie within 2 standard deviations from the mean. μ is the mean time Carson takes to finish 400 meter dash and σ is the standard deviation.




Therefore, the 95% confidence interval is between 60 to 70 seconds
What does it mean?
It means that we are 95% confident that the Carson's mean to finish 400 meter dash is within the interval of (60, 70).
Answer:
range is 9
Step-by-step explanation:
Answer:
5
Step-by-step explanation:
I divided
= 5