O P Malhotra, S K Gupta and, Anubhuti Gangal Solutions for Exercise 1: Exercise

State the following variable is continuous or discrete:

Number of wage earners in a factory.

State whether the following variable is continuous or discrete:

Number of car accidents.

The class marks of a distribution are $2.03, 2.23, 2.43, 2.63, 2.83, 3.03 \mathrm{and} 3.23$.

Determine the class size and the class boundaries.

The following are the monthly rents (in $₹$) of $30$ shops :

$42, 49, 37, 82, 37, 75, 62, 54, 79, 84, 75, 63, 44, 74, 44, 36, 69, 54, 48, 74, 39, 48, 45, 61, 71, 47, 38, 80, 51, 31$.

Using the class intervals of equal width in which one class interval being $40-50$ (excluding $50$), construct a frequency table for the above data.

Construct a frequency table for the following set of data of weights (in grams) of $30$ oranges using equal class intervals one of them being $50-60$ ($60$ not included). 
$$\begin{gathered} 45, 55, 30, 85, 75, 85, 40, 60, 65, 40, 60, 75, 70, 60, 70, \\ 85, 85, 80, 35, 45, 40, 50, 60, 65, 55, 45, 30, 80, 85, 75 \end{gathered}$$

Given below are the Systolic Blood Pressure readings (mm Hg.) made on a person for $30$ days. Construct a frequency distribution for the data using class intervals of equal size, one of them being $150 - 160$ ($160$ not included).
$$\begin{gathered} 165, 159, 190, 150, 171, 182, 165, 141, 135, 155, 192, 152, 155, 145, 145, \\ 160, 175, 179, 178, 120, 125, 128, 152, 135, 142, 128, 140, 130, 130, 160 \end{gathered}$$

Present the following data of the $℅$marks of $60$ students in the form of a frequency table with $10$ classes of equal width, one class being$40 - 49$. 
$$\begin{gathered} 41 17 83 63 54 92 60 58 70 06 67 82 30 44 57 49 34 73 54 63 36 52 32 75 60 38 09 79 28 30 42 \\ 93 43 80 03 32 57 67 24 64 63 11 35 82 10 38 00 4160 32 72 53 92 88 62 55 60 33 40 57 \end{gathered}$$

Thirty $16$year old boys were tested to find their pulse rate. The following figures were obtained for the number of beats per minute. Using the class intervals $51 – 55, 56 - 60,$ etc., of equal width, prepare a frequency table. 
$55, 72, 70, 66, 74, 70, 74, 53, 57, 62, 71, 58, 68, 75, 79, 68, 63, 59, 54, 51, 61, 66, 78, 73, 59, 52, 66, 60, 72, 56$.