Question

Population levels over 5 decades of a small town are given below.

Year	Population
1960	2,50,000
1970	2,80,000
1980	3,40,000
1990	4,20,000
2000	4,90,000

The population of the town in the year 2020 estimated by Arithmetic increase method will be

• A. 5,90,000
• B. 6,90,000
• C. 6,10,000
• D. 5,10,000

Answer 1

The correct option is C 6,10,000

$\text{Average decade increase,}$

$=\frac{30,000+60,000+80,000+70,000}{4}$
$\text{= 60,000}$

$\text{Increase in population over the next 2 decades,}$

$=2\times 60,000$

$\text{= 120,000}$

$\text{Population in year 2020 will be,}$

$P_{2020}=P_{2000}+2\times 60,000$

$=4,90,000+2\times 60,000$

$=6,10,000$