Statistics — Class 9 Mathematics NCERT Solutions (Free)
Free step-by-step NCERT solutions for Class 9 Mathematics chapter "Statistics" — 7 important questions with detailed answers for CBSE board exam preparation.
TL;DR: Free step-by-step NCERT solutions for Class 9 Mathematics chapter "Statistics" — 7 important questions with detailed answers for CBSE board exam prepa…
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Key Questions Covered:
- Define mean, median, and mode for a set of data. For the data set {12, 15, 12…
- For the frequency distribution: Class 0-10 (frequency 5), 10-20 (frequency 8)…
- Construct a frequency distribution table and draw a bar graph for the followi…
- + 4 more questions in the full chapter
Solutions Summary:
| Question | Status |
|---|---|
| Define mean, median, and mode for a set of data. For the … | ✓ Solved |
| For the frequency distribution: Class 0-10 (frequency 5),… | ✓ Solved |
| Construct a frequency distribution table and draw a bar g… | ✓ Solved |
Showing 3 of 7 questions
Q1: Define mean, median, and mode for a set of data. For the data set {12, 15, 12, 18, 20, 12, 25}, find the mean, median, and mode.
Step 1: Definitions:
Mean: The average of all values in the data set.
Median: The middle value when data is arranged in order.
Mode: The value that appears most frequently.
Step 2: Given data set: {12, 15, 12, 18, 20, 12, 25}
Number of values (n) = 7
Step 3: Calculate MEAN:
Mean = (Sum of all valu...
Q2: For the frequency distribution: Class 0-10 (frequency 5), 10-20 (frequency 8), 20-30 (frequency 12), 30-40 (frequency 7), 40-50 (frequency 3). Find the mean of the grouped data.
Step 1: Create frequency distribution table:
Class | Midpoint (x) | Frequency (f) | f×x
0-10 | 5 | 5 | 25
10-20 | 15 | 8 | 120
20-30 | 25 | 12 | 300
30-40 | 35 | 7 | 245
40-50 | 45 | 3 | 1...
Q3: Construct a frequency distribution table and draw a bar graph for the following data: Marks 40, 45, 50, 55, 60, 50, 45, 60, 65, 70, 60, 55, 50, 65, 70, 70. Use class intervals 40-50, 50-60, 60-70, 70-80.
Step 1: Raw data:
40, 45, 50, 55, 60, 50, 45, 60, 65, 70, 60, 55, 50, 65, 70, 70
(Total: 16 values)
Step 2: Count frequencies for each class:
Class 40-50: 40, 45, 45, 50, 50, 50 → Frequency = 6
Class 50-60: 55, 55, 60, 60, 60 → Frequency = 5
Class 60-70: 65, 65, 70, 70, 70 → Frequency = 5
Class 70-...
Showing 3 of 7 questions. Visit the full page for complete solutions.