NCERT Solutions Exploring Society: India and Beyond Chapter 4 Making your own timeline — LET'S EXPLORE
Book page 65 Updated on2026-09-05
Q1.
Create a timeline stretching from 1900 CE to the current year and place the dates of birth of your grandparents, parents, siblings and yourself. Also, mark the years that the 20th century CE begins with and ends with.
Answer
The dates on this timeline must be your family's own. Here is how to build it properly, plus the two answers that are the same for everybody.
The two fixed answers first:
Centuries CE are counted from the year 1 CE, in blocks of 100:
1st century CE = 1 – 100 • 2nd century CE = 101 – 200 • … • 20th century CE = 19 × 100 + 1 to 20 × 100
The 20th century CE begins with 1901 and ends with 2000
(The 21st century CE therefore begins with 2001 and ends with 2100 — exactly as the book says.)
How to draw the timeline:
Take a long strip of paper or a full page turned sideways. Mark 1900 at the left end and the current year at the right end.
Divide the line into equal ten-year (decade) steps: 1900, 1910, 1920 … This keeps the scale honest, so a long gap on the paper really is a long gap in time.
Write each birth year on the line with a small tick, and the person's name above or below it.
Mark 1901 and 2000 in a different colour and label them “20th century CE begins” and “20th century CE ends”.
Below the line, work out each person's age or the gap between two generations by simple subtraction — both dates are CE, so you just subtract.
A family timeline from 1900 CE to the present, drawn to a decade scale. The two red lines are the fixed answers — the 20th century CE begins with 1901 and ends with 2000.
Why the 20th century does not begin in 1900: the counting starts at 1 CE, not 0 CE — the same missing year zero as before. Years 1 to 100 make the 1st century, so years 1901 to 2000 make the 20th. The year 1900 is the last year of the 19th century, and 2000 was the last year of the 20th.
Try this: once your timeline is drawn, measure the gaps. If your grandmother was born in 1950 and you in 2013, that is 2013 – 1950 = 63 years — and your whole family tree fits inside a single century, while the chapter's Fig. 4.3 covers 300,000 years. That contrast is the real lesson of the exercise.