Step 1: Formula for Mode for Grouped Data.
The formula for finding the mode for grouped data is: \[ \text{Mode} = l - \left[ \frac{f_1 - f_0}{2f_1 - f_0 - f_2} \right] \times h \] where:
\( l \) is the lower boundary of the modal class,
\( f_1 \) is the frequency of the modal class,
\( f_0 \) is the frequency of the class preceding the modal class,
\( f_2 \) is the frequency of the class succeeding the modal class,
\( h \) is the class width.
Step 2: Understanding the Formula.
This formula helps us find the mode when the data is grouped into class intervals. The mode is adjusted based on the frequencies of the modal class and its neighboring classes.
Step 3: Conclusion.
Thus, the correct formula for finding the mode for grouped data is: \[ \text{Mode} = l - \left[ \frac{f_1 - f_0}{2f_1 - f_0 - f_2} \right] \times h \]
Class Interval | 50-70 | 70-90 | 90-110 | 110-130 | 130-150 | 150-170 |
---|---|---|---|---|---|---|
Number of Students | 15 | 21 | 32 | 19 | 8 | 5 |
Marks | 0-5 | 5-10 | 10-15 | 15-20 | 20-25 |
---|---|---|---|---|---|
No. of students | 10 | 18 | 42 | 13 | 7 |
The following frequency distribution gives the monthly consumption of electricity of 68 consumers of a locality. Find the median, mean and mode of the data and compare them
Monthly consumption | Number of consumers |
---|---|
65 - 85 | 4 |
85 - 105 | 5 |
105 - 125 | 13 |
125 - 145 | 20 |
145 - 165 | 14 |
165 - 185 | 8 |
185 - 205 | 4 |