Can someone help me with this statistics word question

Question

Fifty 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 Relative Frequency

 

1                                        30                                    0.6

 

 

2                                        15

 

 

3

 

 

A.) Fill in the blanks

 

 

1                   30                       30/50 or 0.6                      0.6

 

2                   15                       15/50 or 0.3                      0.6+0.3 = 0.9

 

3

 

 

B.) What percent of students take exactly 2 courses?

 

C.) What percent of students take one or two courses?

 

From the information I was given I was only able to come up with the second part of the blanks I am not sure what I am supposed to put for number three since there are no numbers to begin with. And if I did it correctly then the answer for B would be 0.3 while C would be 0.9? If someone could help me that would be great. 

Answer 1

In the frequency column, for 3 put 5, thus making the total # of students equal to the stated 50.

 

In the relative frequency column, you're right about 0.3 (opposite 2 classes); then opposite 3 classes, the relative frequency would be 0.1 -- thus the corresponding cumulative frequencies are .9 and 1.0