Question 1

Q1: Which of the following alternatives is true? (i) The class midpoint is equal to: (a) The average of the upper class limit and the lower class limit. (...

Accepted Answer

(i) The correct alternative is (a) The average of the upper class limit and the lower class limit. As stated in the chapter, the formula for the class midpoint is: Class Mid-Point = (Upper Class Limit + Lower Class Limit) / 2. (ii) The correct alternative is (b) Bivariate Distribution. The chapter d...

Question 2

Q10: Prepare a frequency distribution by inclusive method taking class interval of 7 from the following data. 28 17 15 22 29 21 23 27 18 12 7 2 9 4 1 8 3 1...

Accepted Answer

To prepare a frequency distribution using the inclusive method with a class interval of 7, we first need to determine the range of the data and then form the classes.    Smallest Value = 1    Largest Value = 37 The class intervals will be formed in an inclusive manner (e.g., 1-7, 8-14, etc.). Freque...

Question 3

Q11: "The quick brown fox jumps over the lazy dog" Examine the above sentence carefully and note the numbers of letters in each word. Treating the number o...

Accepted Answer

First, we list each word in the sentence and count the number of letters in it. The number of letters is our discrete variable.    The: 3 letters    quick: 5 letters    brown: 5 letters    fox: 3 letters    jumps: 5 letters    over: 4 letters    the: 3 letters    lazy: 4 letters *   dog: 3 letters T...

Question 4

Q2: Can there be any advantage in classifying things? Explain with an example from your daily life.

Accepted Answer

Yes, there are significant advantages in classifying things. Classification is the process of arranging or organising things into groups or classes based on some common criteria. This process brings order to disorganised data or items, making them easier to manage and understand. The main advantages...

Question 5

Q3: What is a variable? Distinguish between a discrete and a continuous variable.

Accepted Answer

A variable is a characteristic or phenomenon which is capable of being measured and changes its value over time. For example, the marks of students in an examination are a variable because they differ from one student to another. Variables can be distinguished into two types: discrete and continuous...

Question 6

Q4: Explain the 'exclusive' and 'inclusive' methods used in classification of data.

Accepted Answer

The 'exclusive' and 'inclusive' methods are two ways of forming class intervals in a frequency distribution. Exclusive Method:    In this method, the upper limit of one class interval is the same as the lower limit of the next class interval (e.g., 10-20, 20-30, 30-40).    An item with a value equal...

Question 7

Q5: Use the data in Table 3.2 that relate to monthly household expenditure (in Rs) on food of 50 households and (i) Obtain the range of monthly household...

Accepted Answer

(i) Range of monthly household expenditure on food: First, we need to find the highest and lowest values from Table 3.2.    Highest value (Maximum expenditure) = Rs 5090    Lowest value (Minimum expenditure) = Rs 1007 The range is the difference between the highest and the lowest value. Range = High...

Question 8

Q6: In a city 45 families were surveyed for the number of Cell phones they used. Prepare a frequency array based on their replies as recorded below. 1 3 2...

Accepted Answer

A frequency array is used to classify the data of a discrete variable. Here, the variable is the 'number of cell phones', which is a discrete variable. The frequency array is prepared by counting the number of times each value occurs in the data. Note: The question states that 45 families were surve...

Question 9

Q7: What is 'loss of information' in classified data?

Accepted Answer

'Loss of information' refers to an inherent shortcoming of classifying raw data into a frequency distribution. While classification summarises the data to make it concise and comprehensible, it does so at the cost of losing the details found in the original raw data. When data is grouped into classe...

Question 10

Q8: Do you agree that classified data is better than raw data? Why?

Accepted Answer

Yes, I agree that for the purpose of analysis and drawing conclusions, classified data is better than raw data. Raw data, especially when it is large, is highly disorganised and cumbersome to handle. It is difficult to draw any meaningful conclusions from a large set of unorganised numbers. Classifi...

Question 11

Q9: Distinguish between univariate and bivariate frequency distribution.

Accepted Answer

The main distinction between a univariate and a bivariate frequency distribution lies in the number of variables they describe. Univariate Frequency Distribution:    A univariate frequency distribution deals with a single variable.    It shows how the different values of that one variable are distri...

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