# The following table gives the life times of 400 neon lamps:

(i) Represent the given information with the help of a histogram.

(ii) How many lamps have a life time of more than 700 hours?

**Solution:**

(i) From the data given we plot the histogram as:

- Represent the lifetime (in hours) in x-axis.
- Represent the number of lamps in y-axis.
- Class intervals are from 300-400 till 900-1000
- Take “1 unit = 10 lamps” on y–axis as the lowest value of frequency is 14 and the highest is 86.
- Also, since the first interval is starting from 300 and not ‘0’, we show it by marking a ‘kink’ or a break on the x-axis.

It can be seen from the above graph that:

(ii) The number of neon lamps having their lifetime of more than 700 hours lies in the class intervals 700 – 800, 800 – 900, 900 – 1000.

Hence, their corresponding frequencies when added up will be (74 + 62 + 48) = 184 lamps.

**☛ Check: **NCERT Solutions for Class 9 Maths Chapter 14

**Video Solution:**

## The following table gives the lifetimes of 400 neon lamps: i) Represent the given information with the help of a histogram. (ii) How many lamps have a lifetime of more than 700 hours?

NCERT Solutions for Class 9 Maths Chapter 14 Exercise 14.3 Question 5

**Summary:**

The data of lifetimes of 400 neon lamps is given. We have found that number of neon lamps having their lifetime of more than 700 hours lies in the class intervals “700 – 800, 800 – 900, 900 – 1000”. Hence, their corresponding frequencies when added up will be (74 + 62 + 48) = 184 lamps.

**☛ Related Questions:**

- A survey conducted by an organization for the cause of illness and death among the women between the ages 15 - 44 (in years) worldwide, found the following figures (in %): (i) Represent the information given above graphically,(ii) Which condition is the major cause of women’s ill health and death worldwide?(iii) Try to find out, with the help of your teacher, any two factors which play a major role in the cause in (ii) above being the major cause.
- The following data on the number of girls (to the nearest ten) per thousand boys in different sections of Indian society is given below. i) Represent the information above by a bar graph. ii) In the classroom discuss what conclusions can be arrived at from the graph.
- Given below are the seats won by different political parties in the polling outcome of a state assembly elections: i) Draw a bar graph to represent the polling results. ii) Which political party won the maximum number of seats?

visual curriculum