On the basis of this bar graph, what may be a few questions you may ask your friends?
Answer
Good questions are the ones a reader can answer from the graph itself. Here are some you can ask:
Population of India, 1951 to 2001. One unit length stands for 10 crore people.
Reading questions — What was the population of India in 1971? (54 crore) In which year did it first cross 100 crore? (2001)
Comparing questions — Was the population in 1991 more than double that of 1951? (84 vs 72 — yes, just about.) Which two decades look almost the same in height?
Difference questions — How much did the population grow between 1961 and 1981? (68 − 44 = 24 crore)
Trend questions — Is the graph rising or falling? Are the steps getting bigger or smaller as we move right?
Prediction questions — Using the pattern, guess the population in 2011. (About 120 crore — the actual figure was close to 121 crore.)
Scale questions — Why did we take 1 unit = 10 crore instead of 1 unit = 1 person?
Tip: a question like “Why did the population increase?” cannot be answered from the graph — the graph shows what happened, not why. Such questions need other information.
Q2.
How much did the population of India increase over 50 years? How much did the population increase in each decade?
Answer
Over the 50 years from 1951 to 2001:
102 crore − 36 crore = 66 crore
That is, India added about 66 crore people in 50 years — nearly three times its 1951 population became the 2001 population.
Decade by decade, subtract each value from the next:
Decade
Population at start
Population at end
Increase (crore)
1951 – 1961
36
44
8
1961 – 1971
44
54
10
1971 – 1981
54
68
14
1981 – 1991
68
84
16
1991 – 2001
84
102
18
Total
—
—
66
8 + 10 + 14 + 16 + 18 = 66 crore ✔ — the decade increases add up to the 50-year increase.
What the numbers show: the increase itself grew every decade — 8, then 10, 14, 16, 18. So the graph does not rise in equal steps; each step is taller than the one before it. That is why the bars seem to climb faster and faster towards the right.