Question

4. The earth's population is 7.8 billion today. What is the percent change in the lastdecade if the global population was 70 billion in 2011?

Answer 1

Solution:

Percentage change equals the change in value divided by the absolute value of the original value, multiplied by 100. That is:

$\frac{V2-V1}{\text{I }V1\text{ I}}\text{ x 100\%}$

in this case, we have that:

V1 = 7 billion = 7,000,000,000.

V2 = 7.8 billion = 7,800,000,000.

then, we get:

$\frac{7800000000-7000000000}{\text{I }7000000000\text{I}}\text{ x 100\% = }11.4$

then, the correct answer is:

11.4%