Find the mode of the given data (correct to two places of decimal).
| Class interval | 0-6 | 6-12 | 12-18 | 18-24 | 24-30 |
| Frequency | 8 | 7 | 5 | 9 | 4 |
Correct Answer :
20.67
Solution :
The correct answer is 20.67.
Step-by-step Explanation:
1. Identify the Modal Class:
The mode of grouped data lies in the class interval with the highest frequency.
Looking at the given frequency distribution:
• Class interval 0-6 has frequency 8
• Class interval 6-12 has frequency 7
• Class interval 12-18 has frequency 5
• Class interval 18-24 has frequency 9
• Class interval 24-30 has frequency 4
The maximum frequency is 9, which corresponds to the class interval 18-24. Therefore, the modal class is 18-24.
2. Formula for Mode of Grouped Data:
The formula to calculate the mode for grouped data is:
Where:
• L = Lower limit of the modal class = 18
• f1 = Frequency of the modal class = 9
• f0 = Frequency of the class preceding the modal class = 5
• f2 = Frequency of the class succeeding the modal class = 4
• h = Width of the class interval = 24 - 18 = 6
3. Calculation:
Substitute these values into the mode formula:
Simplify the terms inside the fraction:
Thus, the mode of the given data correct to two decimal places is 20.67.
Access expert-curated educational resources and study materials—completely free.
Create, conduct, and manage professional online assessments with Mindyard. Perfect for teachers and institutes.
Copyright © 2026 Mindyard. All Rights Reserved.