Question

The heights (in cm) of students of a class is tabulated below.
$\begin{array}{cc}\text{Height}& \text{Number of students}\\ 150-154& 4\\ 155-159& 3\\ 160-164& 2\\ 165-169& 1\\ 170-174& 2\\ 175-179& 2\\ 180-184& 4\\ 185-189& 2\\ Total& 20\end{array}$
Identify the correct option (s).

• A. The class distribution is discontinuous
• B. Number of students having height in range of 160-174 cm is 5
• C. The data can not be changed into continuous class interval form
• D. The range of data is 40

Answer 1

Answer: (A), (B), (D)

The correct options are
A

The class distribution is discontinuous

B

Number of students having height in range of 160-174 cm is 5

D

The range of data is 40

In the given table, the upper limit of a class does not coincide with the lower limit of the succeeding class, so the class intervals are not continuous and option A is correct.
Also the number of students in the range of 160 cm -174 cm = 2+1+2 = 5. Hence, option B is correct.
Also, any data having discontinuous class intervals can be converted into one with continuous class intervals. Hence, C is incorrect.
Range of data = Total width of data = 189-150 = 39.