Question

8)

In 2007, the population of North America was approximately 5.15 x 108 people and the population of South America was approximately 3.04 x 108 people. What is the combined population of North and South America for this year?
A) 8.19 x 1016 people
Eliminate
B) 8.19 x 109 people
C) 8.19 x 108 people
D) 8.19 x 1064 people

Answer 1

You can add both units together: Namely you can add 5.15 to 3.04 = which equals to 8.19 and the average of 108 + 180 = 360/2
which means its an averige of 180.
so the correct anwser is C) 8.19 x 108 people

Answer 2

The answer is 8.19 x 108 (letter C).

Explanation:

In order to determine the answer, we have to know about factorization.

In any math expression, sometimes there are equal terms. A term is just a variable and a coefficient. Also a variable may be just a number.

When there are two equal numbers or two equal variables, we can factorize them. This factor will multiply other expression inside in the parentheses.

In this case, we have two numbers, 5.15 x 108 and 3.04 x 108. Both numbers have the 108 equal. Also, we have to add the North America population with the South America population.

Factoring by 108:

`5.15*108+3.04*108\\108*(5.15+3.04)\\8.19*108`

Finally, the answer is 8.19 x 108 (letter C).