Final answer:
The missing frequency for students taking 3 courses is 30 and the relative frequencies for taking 2 courses and 3 courses are 0.3 and 0.5 respectively when rounded to the nearest tenth. The table is completed using the total number of students, which is 65.
Step-by-step explanation:
To complete the table with the missing frequency and relative frequencies, we need to consider that the total number of students surveyed is 65. Given that there are 15 students taking 1 course and the relative frequency is 0.2, we can calculate the relative frequency for the 20 students taking 2 courses. The relative frequency is calculated by dividing the frequency by the total number of students. Therefore, for 2 courses, the relative frequency is 20/65 which rounds to 0.3 when rounded to the nearest tenth.
With 15 students taking 1 course and 20 students taking 2 courses, this leaves us with 65 - 15 - 20 = 30 students that must be taking 3 courses. To find the relative frequency for 3 courses: 30/65 = 0.46 which rounds to 0.5 when rounded to the nearest tenth. Now we have all the missing values in the table.
The completed table shows that 15 students are taking 1 course with a relative frequency of 0.2, 20 students are taking 2 courses with a relative frequency of 0.3 and 30 students are taking 3 courses with a relative frequency of 0.5, adding to a total of 65 students surveyed.