Question

The heights (in cm) of students of a class is tabulated below.
$\begin{array}{cc}\text{Height}& \text{Number of students}\\ 150-154& 4\\ 155-159& 3\\ 160-164& 2\\ 165-169& 1\\ 170-174& 2\\ 175-179& 2\\ 180-184& 4\\ 185-190& 2\end{array}$
The cumulative frequency for the class interval 179.5 - 184.5 is ?

• A. 20
• B. 18
• C. 2
• D. 6

Answer 1

The correct option is B

18

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.

$\begin{array}{ccc}\text{Height}& \text{Number of students}& \text{Cumulative Frequency}\\ 149.5-154.5& 4& 4\\ 154.5-159.5& 3& 7\\ 159.5-164.5& 2& 9\\ 164.5-169.5& 1& 10\\ 169.5-174.5& 2& 12\\ 174.5-179.5& 2& 14\\ 179.5-184.5& 4& 18\\ 184.5-190.5& 2& 20\end{array}$