Textmsg Statistics
1. **Problem statement:**
We have frequency data of the number of text messages sent by students as follows:
- 3 messages: 3 students
- 4 messages: 4 students
- 5 messages: 8 students
- 6 messages: 7 students
- 7 messages: 6 students
- 8 messages: 3 students
We need to find:
(a) Total number of students in the class.
(b) The median number of text messages sent.
(c) The modal number of text messages sent.
2. **(a) Number of students:**
Add up all the frequencies:
$$3 + 4 + 8 + 7 + 6 + 3 = 31$$
So, there are **31 students** in total.
3. **(b) Median number of text messages:**
The total number of students is 31, so the median is the value at the $$\frac{31 + 1}{2} = 16$$th student when ordered by number of messages.
List cumulative frequencies:
- Up to 3 messages: 3 students
- Up to 4 messages: 3 + 4 = 7 students
- Up to 5 messages: 7 + 8 = 15 students
- Up to 6 messages: 15 + 7 = 22 students
The 16th student falls in the 6 messages group because 15 < 16 \leq 22.
Thus, the median number of text messages is **6**.
4. **(c) Modal number of text messages:**
The mode is the value with the highest frequency.
Frequencies:
- 3 messages: 3
- 4 messages: 4
- 5 messages: 8
- 6 messages: 7
- 7 messages: 6
- 8 messages: 3
The highest frequency is 8 at 5 messages.
So, the mode is **5**.
**Final answers:**
(a) 31
(b) 6
(c) 5