An insect population grows at a rate of 25% per year. if its initial population is 4.2 million what will be its population in three year?

The population after 3 years would be 8.20 millions.

Step-by-step explanation:

Given,

Initial population = I = 4.2 million

Growing rate = r = 25%

If the initial population and growing rate is given, the formula to calculate the population (x) after n years would be:

By putting the values in the equation, we get

The population after 1st year (x1) would be

x1 = 5.25 million

Similarly,

x2 = 6.56 million

x3 = 8.20 million

Hence, the population after 3 years would be 8.20 millions.

But, if you are asking about the total population at that time. It would be

I + x1 + x2 + x3 = 24.21 million

it's d.

step-by-step explanation:

because: -1(4x + 1y) +2 (1x-3y) distribute each number into the parenthesis.

then you would get: -4x - 1y + 2x -6y combine like terms

and get: 2x -7y

hope my answer has you if not then i'm sorry.