Determine the modal class for the frequency distribution given below is:
`{:("Class interval",0-20,20-40,40-60,60-80,80-100),("Number of workers",15,18,21,29,17):}`

Answer

To determine the modal class for the given frequency distribution, we will follow these steps:

### Step 1: Identify the Class Intervals and Frequencies
We have the following class intervals and their corresponding frequencies:
- Class interval 0-20: Frequency 15
- Class interval 20-40: Frequency 18
- Class interval 40-60: Frequency 21
- Class interval 60-80: Frequency 29
- Class interval 80-100: Frequency 17

### Step 2: Find the Maximum Frequency
Next, we need to find the maximum frequency from the given data. We will compare the frequencies:
- 15 (for 0-20)
- 18 (for 20-40)
- 21 (for 40-60)
- 29 (for 60-80)
- 17 (for 80-100)

The maximum frequency is **29**.

### Step 3: Identify the Class Interval Corresponding to the Maximum Frequency
Now, we need to find the class interval that corresponds to this maximum frequency of 29. From our data, we see that the class interval with the frequency of 29 is **60-80**.

### Step 4: State the Modal Class
The modal class is the class interval with the highest frequency. Therefore, the modal class is **60-80**.

### Final Answer
The modal class for the given frequency distribution is **60-80**.

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