Question

distribution of grades over the past two years is as follows: GRADE NUMBER OF STUDENTS A 80 B 75 C 90 D 30 F 25 Total 300 If this past distribution is a good indicator of future grades, what is the probability of a student receiving a C in the course

Answer 1

The probability of a student receiving a C in the course is p=0.3.

Explanation:

We have a absolute frequency for each of the grades (A to F), of a total of 300 course tests.

It is assumed that this sample gives a dood estimation of the distribution of the grades. Then, we can estimate the probability of obtaining a C in the course usign the relative frequency for C.

The relative frequency is calculated as the division between the absolute frequency (in this case, 90 for a C grade) and the size of the sample (in this example, 300).

`p_C=(X_C)/(N)=(90)/(300)=0.3`