Hours they will glow and the results are
represented in the following histogram.
1000 bulbs were tested for the number of
Study the histogram and answer the given
questions.
(i) What is the size of the class interval?
(ii) Find the range of hours in which
maximum number of bulbs glow.
(iii) A bulb is considered defective if it
glows for less than 40 hours. Find the
number of defective bulbs.
(iv) How many bulbs glow between 80
and 120 hours?
(v) How many bulbs glow for more than
200 hours?
