1. What is the mode of the data set: 5, 7, 9, 7, 6, 5, 5?
Answer:
Explanation:
The mode is the number that appears most frequently. Here, '5' appears three times, more than any other number.
2. The mean of five numbers is 20. If four of these numbers are 15, 20, 25, and 30, what is the fifth number?
Answer:
Explanation:
The sum of all five numbers is 20 x 5 = 100. The sum of the first four numbers is 90. Thus, the fifth number is 100 – 90 = 10.
3. Which of the following is NOT a measure of central tendency?
Answer:
Explanation:
Range is a measure of dispersion, not central tendency. It gives the spread of the data.
4. If the median of a data set is 12, it implies:
Answer:
Explanation:
The median divides the data set into two equal halves. Half of the data points are below the median and half are above it.
5. The mean of a data set is affected by:
Answer:
Explanation:
Extreme values, or outliers, can greatly influence the mean, making it larger or smaller than the central values.
6. In a frequency distribution table, the 'class width' is:
Answer:
Explanation:
The class width is the difference between the upper and lower boundaries of a class.
7. In a class interval of 10-20, if the lower limit is 10, the upper limit is:
Answer:
Explanation:
In the given class interval, the upper limit is clearly mentioned as 20.
8. A pie chart is most useful for:
Answer:
Explanation:
Pie charts visually represent parts of a whole, making it easier to compare different sections.
9. The median of an odd number of data points can be found by:
Answer:
Explanation:
With an odd number of data points, the median is simply the middle value.
10. Which of the following statements is true about the mode?
Answer:
Explanation:
A data set can be bimodal (two modes) or even multimodal (more than two modes).
11. What is the range of the data set: 5, 8, 12, 20, 25?
Answer:
Explanation:
The range is the difference between the highest and lowest values. Here, it is 25 – 5 = 20.
12. Which of the following measures is most affected by extreme values?
Answer:
Explanation:
The mean is highly sensitive to outliers or extreme values, while the median and mode are more robust.
13. The class mark of the class interval 30-40 is:
Answer:
Explanation:
The class mark is the midpoint of a class, which is (30+40)/2 = 35.
14. A histogram is used to represent:
Answer:
Explanation:
A histogram is a graphical representation of the distribution of a dataset, primarily used for numerical data.
15. The mode is the value that:
Answer:
Explanation:
By definition, the mode is the value that appears most often.
16. The measure that gives the spread or dispersion of data is:
Answer:
Explanation:
The range provides an indication of how spread out the values are in a data set.
17. The class intervals 10-20, 20-30, 30-40 are:
Answer:
Explanation:
Exclusive class intervals do not include the upper class boundary of one interval and the lower class boundary of the next.
18. If the mean of seven numbers is 30 and one of the numbers is excluded, the mean of the remaining six numbers is:
Answer:
Explanation:
Without knowledge about the number being excluded, we cannot determine the direction in which the mean will shift.
19. Which of the following is a graphical representation of data where each data item is shown as a dot above a number line?
Answer:
Explanation:
A dot plot is a simple representation where each data point is shown as a dot.
20. The median is a measure that:
Answer:
Explanation:
The median divides the data set into two equal parts, with half the data points being less than the median and half being greater.