The following data : 2, 5, 15, 25, 20, 12, 8, 7, 6, 16, 21,17, 30, 32, 23, 40, 51, 15, 2, 9, 57, 19, 25 is grouped in the classes 0 –5, 5 –10, 10 –15 etc. Find the frequency of the class 20 –25.

Options

A. `5`
B. `4`
C. `3`
D. `2`

Answer

To find the frequency of the class 20-25 from the given data, we will follow these steps:

### Step-by-Step Solution:

1. **List the Data**: Write down the given data points.
- Data: 2, 5, 15, 25, 20, 12, 8, 7, 6, 16, 21, 17, 30, 32, 23, 40, 51, 15, 2, 9, 57, 19, 25

2. **Define the Classes**: Identify the classes based on the problem statement.
- Classes:
- 0-5
- 5-10
- 10-15
- 15-20
- 20-25
- 25-30
- 30-35
- 35-40
- 40-45
- 45-50
- 50-55
- 55-60

3. **Count Frequencies for Each Class**:
- For each class, count how many data points fall into that range:
- **0-5**: 2, 5 (Count = 2)
- **5-10**: 8, 7, 6, 9 (Count = 4)
- **10-15**: 15, 12, 15 (Count = 3)
- **15-20**: 16, 19 (Count = 2)
- **20-25**: 20, 21, 25, 23 (Count = 4)
- **25-30**: 25, 30 (Count = 2)
- **30-35**: 32 (Count = 1)
- **35-40**: 40 (Count = 1)
- **40-45**: None (Count = 0)
- **45-50**: 51 (Count = 1)
- **50-55**: None (Count = 0)
- **55-60**: 57 (Count = 1)

4. **Identify the Frequency for the Class 20-25**:
- From the count above, the frequency for the class 20-25 is **4**.

5. **Conclusion**:
- The frequency of the class 20-25 is **4**.

### Final Answer:
The frequency of the class 20-25 is **4**.