In a test, the marks obtained by $100$ students (out of $50$) are given below:

| Marks obtained | $0 - 10$ | $10 - 20$ | $20 - 30$ | $30 - 40$ | $40 - 50$ |
|----------------|----------|-----------|-

Question

In a test, the marks obtained by $100$ students (out of $50$) are given below:

| Marks obtained | $0 - 10$ | $10 - 20$ | $20 - 30$ | $30 - 40$ | $40 - 50$ |
|----------------|----------|-----------|-----------|-----------|----------|
| Number of students | $12$ | $23$ | $34$ | $25$ | $6$ |

Find the mean marks of the students.

Accepted Answer

Step 1: | Marks Obtained | Number of students ($f_i$) | $x_i$ | $f_i x_i$ |
|----------------|---------------------------|--------|----------|
| $0 - 10$ | $12$ | $5$ | $60$ |
| $10 - 20$ | $23$ | $15$ | $345$ |
| $20 - 30$ | $34$ | $25$ | $850$ |
| $30 - 40$ | $25$ | $35$ | $875$ |
| $40 - 50$ | $6$ | $45$ | $270$ |
| **Total** | $100$ | | $2400$ |
Step 2: Mean $= \frac{\sum f_i x_i}{\sum f_i} = \frac{2400}{100}$
Step 3: $= 24$

Question

Solution