Statistics

Topics in this chapter

• Data and Frequency Distributions
• Arithmetic Mean of Grouped Data
• Median and Cumulative Frequency
• Mode and Empirical Relationship
• Ogives and Statistical Graphs
• Missing and Incorrect Data

Cheat sheet

Practice questions

1. Question 1Q-8278DF

   For the following distribution, what is the lower limit of the modal class? Marks: 0-10, 10-20, 20-30, 30-40, 40-50 Number of students: 3, 12, 20, 15, 5

   1. A.10
   2. B.20
   3. C.30
   4. D.0
   See the answer and solution
2. Question 2Q-C24C63

   The relationship between mean, median, and mode for a moderately skewed distribution is given by:

   1. A.$\text{Mode} = 3 \text{Median} - 2 \text{Mean}$
   2. B.$\text{Mode} = 2 \text{Median} - 3 \text{Mean}$
   3. C.$\text{Median} = 3 \text{Mode} - 2 \text{Mean}$
   4. D.$\text{Mean} = 3 \text{Median} - 2 \text{Mode}$
   See the answer and solution
3. Question 3Q-D315AD

   If the mean of observations $x, x+3, x+5, x+7, ext{and } x+10$ is $9$, find the mean of the last three observations.

   1. A.10.33
   2. B.11.33
   3. C.12.33
   4. D.13.33
   See the answer and solution
4. Question 4Q-6B4A10

   While computing the mean of grouped data using the formula $\bar{x} = a + \left(\frac{\sum f_i u_i}{\sum f_i}\right) \times h$, what does $u_i$ represent?

   1. A.$x_i - a$
   2. B.$\frac{x_i - a}{h}$
   3. C.$h(x_i - a)$
   4. D.$x_i + a$
   See the answer and solution
5. Question 5Q-FCFB4D

   If the median of a series of data is $50$ and the sum of frequencies is $80$, what is the median class if the cumulative frequency just greater than $N/2$ is $60$ corresponding to interval $40-60$?

   1. A.$20-40$
   2. B.$40-60$
   3. C.$60-80$
   4. D.$30-50$
   See the answer and solution