NCERT Solutions Ganita Prakash (Part 2) Chapter 5 –119Section 5.2 Visualising and Interpreting Data — In-text Questions
Book page 116 Updated on2026-09-05
Q1.
Now, observe the following graph. Do both these graphs represent the same information?
Answer
Yes — exactly the same numbers, drawn in two different ways. Both show the monthly maximum temperature in Kerala and Punjab through 2023, with the months along the horizontal axis and the temperature in °C up the vertical axis.
Clustered-column graph
Line graph
How a value is shown
Height of a bar
Height of a marked point
What stands out
Comparing the two states month by month
How each state changes through the year
Reading a trend
Eye has to hop from bar top to bar top
The joining line shows the trend directly
Why the line graph reads better here: the data is a sequence in time, and the joining segments turn ‘rising’, ‘flat’ and ‘falling’ into shapes you can take in at a glance. Punjab’s hump and Kerala’s almost-flat line are obvious in the line graph; in the column graph the same fact has to be assembled from 24 separate bar heights.
Tip: the line between two months is only a guide for the eye. There was no single ‘temperature’ midway between January and February — the graph gives one figure per month, and the segment merely links them.
Q2.
How do we get the maximum temperature over a month in a state?
Answer
A state is large, so no one thermometer speaks for it. A few weather stations spread across the state record the local temperature regularly. For a given month, the state’s monthly maximum is taken as the largest of all the values recorded at those stations during that month.
Why knowing this matters: once you know how a number was produced you can judge what it can and cannot tell you. This figure is a peak, not a typical day — Punjab’s 38 °C in June does not mean every June day was 38 °C, or that every part of Punjab reached it. It also means the answer depends on where the stations happen to be: more stations in the hottest district would push the recorded maximum up. Asking how data was collected is how you spot such limitations and bias.
Q3.
What thoughts or questions occur to you?
Answer
Some questions worth carrying further, of the kind the chapter is inviting:
Why are the two trends so different? Punjab is far inland and far north, so it swings from about 19 °C in January to 38 °C in June. Kerala sits near the equator with the sea on one side, and the sea heats and cools slowly, so its monthly maxima stay between about 29 °C and 33 °C all year.
What decides a region’s temperature? Latitude, distance from the sea, height above sea level, and the monsoon — Kerala’s dip to about 29 °C comes in July, its wettest month, when cloud and rain keep the days cool.
Which other states would look like Punjab? Try Rajasthan, Haryana, Delhi and Uttar Pradesh — all inland and northern.
What would the monthly minimum temperatures look like? Punjab’s winter minima would drop very low, so the gap between its two curves would be much wider than Kerala’s.
Is the difference between the two states growing over the years? That needs data from several years, not one.
Try This: pick your own district, find its monthly maximum temperatures for last year, and draw them on the same axes. Does your line behave more like Kerala’s or like Punjab’s?