Question

The following table gives the lifetimes of 400 neon lamps:

$\begin{array}{cccccccc}\text{Lifetime}& 300-400& 400-500& 500-600& 600-700& 700-800& 800-900& 900-1000\\ \text{(in hr)}& & & & & & & \\ \text{Number}& 14& 56& 60& 86& 74& 62& 48\\ \text{of lamps}& & & & & & & \end{array}$
(i) Represent the given information with the help of a histogram.
(ii) How many lamps have a lifetime of more than 700 hours?

Answer 1

(i) Histogram is as follows:



(ii) Number of lamps having lifetime more than 700 hours = 74 + 62 + 48 = 184