Age-Sex pyramid of which country is bell shaped?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → Australia
An age-sex pyramid shows the number of males and females in each age group. Its shape tells us how the population is changing.
Option (1) Australia — Correct. Its pyramid is bell shaped and tapers towards the top. Birth and death rates are almost equal, so the population stays nearly constant.
Option (2) Bangladesh — Incorrect. Its pyramid looks like Nigeria’s: a triangle with a wide base. High birth rates give large numbers of people in the lower age groups.
Option (3) Mexico — Incorrect. Mexico, too, has an expanding population, so its pyramid is triangular, not bell shaped.
Option (4) Nigeria — Incorrect. Nigeria is the example of an expanding population. Its triangular pyramid with a wide base is typical of less developed countries.
Note: This question is taken from the pre-rationalised NCERT book. The latest edition (2026-27) does not have this part. An extract of the pre-rationalised NCERT book is given below for the benefit of students.
Pre-rationalised NCERT: “Expanding Populations … The age-sex pyramid of Nigeria as you can see is a triangular shaped pyramid with a wide base and is typical of less developed countries. These have larger populations in lower age groups due to high birth rates. If you construct the pyramids for Bangladesh and Mexico, it would look the same.” “Constant Population … Australia’s age-sex pyramid is bell shaped and tapered towards the top. This shows birth and death rates are almost equal leading to a near constant population.”
Fig. 3.2: Constant Population |
