Question

50 part - time students were asked how many courses they were taking this term. the (incomplete) results are shown below:

# of courses	frequency	relative frequency	cumulative frequency
2	21
3

a. complete the table.
b. what percent of students take exactly three courses? %
hint: hint ( )

Explanation:

Step1: Find total number of students

The total number of students is 50.

Step2: Calculate relative frequency for 2 courses

The frequency for 2 courses is 21. The relative - frequency is $\frac{21}{50}=0.42$.

Step3: Calculate frequency for 3 courses

Let the frequency for 3 courses be $x$. We know that $12 + 21+x=50$. So $x = 50-(12 + 21)=17$.

Step4: Calculate relative frequency for 3 courses

The relative frequency for 3 courses is $\frac{17}{50}=0.34$.

Step5: Calculate cumulative frequency

For 1 course, cumulative frequency is 12. For 2 courses, cumulative frequency is $12 + 21=33$. For 3 courses, cumulative frequency is $12+21 + 17=50$.

Step6: Calculate percentage for part b

The percentage of students taking exactly 3 courses is $\frac{17}{50}\times100\% = 34\%$.

# of Courses	Frequency	Relative Frequency	Cumulative Frequency
2	21	0.42	33
3	17	0.34	50

Answer:

a.

# of Courses	Frequency	Relative Frequency	Cumulative Frequency
2	21	0.42	33
3	17	0.34	50

b. 34%