Question

find out average rate of increase in population which is the first decade has increased 20%, in the second 25% and in third 44% respectively.

Answer 1

Given that,

The population in the first decade has increased 20%, in the second 25% and in third 44% respectively.

To find,

The average rate of increase in population.

Solution,

Let initial population was 100.

When it increased 20 %, $100\times \dfrac{120}{100}=120$

After second year, $120\times \dfrac{125}{100}=150$

After the third year, $150\times \dfrac{144}{100}=216$

Total increase in percentage in three years = 216-100 = 116

Percentage increase in population is

$P\%=\dfrac{116}{100}\times 100\\\\P\%=116\%$

For average rate of increase in population $\dfrac{116}{3}=38.67\%$. Hence, this is the required solution.