Question

the population of a town increases by 12% during the first year and decreases by 10% during second year. if the population at present is 50400, what was the population 2 years ago?

Answer 1

let the population 2 years ago be x
according to question
x(112/100)(90/100)= 50400
x=50000

Answer 2

Answer:

2 years ago the population was 50000

Step-by-step explanation:

Let the original population be x

The population of a town increases by 12% in first year

So, new population = $x+\frac{12}{100}x=x+0.12x=1.12x$

Now The population of a town decreases by 10% during second year.

So, new population = $1.12x-\frac{10}{100}(1.12x) = 1.12x-0.1(1.12x)=1.12x-0.112x=1.008x$

Now we are given that the population at present is 50400

So,$1.008x=50400$

$x=\frac{50400}{1.008}$

$x=50000$

Hence 2 years ago the population was 50000