#### The population of a city increase each year by 4% of what it had been at the beginning of each year. If its present population is 6760000, find:

(i) its population 2 years hence

(ii) its population 2 years ago.

**Solution:**

It is given that

Present population = 6760000

Increase percent = 4% p.a.

(i) We know that

Population 2 years hence = P (1 + r/100)^{2}

Substituting the values

= 6760000 (1 + 4/100)^{2}

By further calculation

= 6760000 × 26/25 × 26/25

= 7311616

(ii) We know that A = 6760000

Population 2 years ago P = A + (1 + r/100)^{2}

Substituting the values

= 6760000 + (1 + 4/100)^{2}

By further calculation

= 6760000 + (26/25)^{2}

= 6760000 × 25/26 × 25/26

= 6250000

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