We have the frequencies for each of the grades. We can estimate the number of students graded by adding all those frequencies. Let's call N the total number of grades:

We have then a total number of grades of 39.
The corresponding relative frequency for a grade is the ratio of the frequency to the total number of "samples", 39 in this case.
Then, for grade A, the relative frequency (RF) will be:

This will be the fraction of the total grades that are A. Represented as a percentage will be 10.26%, rounded to two decimal places.
Now, to complete the table we do the same for the other frequencies:
For grade B:

For grade C:

For grade D:

For grade F:
Answer: 0.01145
Step-by-step explanation:
We use Binomial distribution , where the probability of getting x successes in n trial is given by :-
, p = probability of getting each success in each trial.
As per given
The proportion that a car with a certain protection system will be recovered= p=0.87
n= 8
Let x be the number of cars will be recovered.
Then, the probability that 4 of 8 stolen cars will be recovered:


Hence, the required probability is 0.01145.
Not to good with math but the answer may be B
Answer:
D
Step-by-step explanation:
Look at all possibilities then use all of them then find out which one matches the best.