Question

The table shows the population of the two countries in North America in 2011.

$\begin{array}{ccc}\text{Country}& \text{Canada}& \text{Mexico}\\ \text{Population}& 3.38\times {10}^7& 1.1\times {10}^8\end{array}$

Using the population table above, how many more people live in Mexico than in Canada?

Answer 1

Detailed step-by-step solution:
To see how many more people live in Mexico than in Canada, we need to calculate the difference between their populations. I.e.,
Desired number of people $=$ (Population of Mexico $-$ Population of Canada)
$\Rightarrow 1.1\times {10}^8-3.38\times {10}^7=1.1\times {10}^{7+1}-3.38\times {10}^7$ (the exponent of $10$ should be same while subtracting)
$=1.1\times 10\times {10}^7-3.38\times {10}^7$ (using property of product of powers, i.e., $a^m\times a^n=a^{m+n}$)
$=(11-3.38)\times {10}^7$ (using distributive property, i.e., $a\times (b-c)=a\times b-a\times c)$
$=7.62\times {10}^7$
$\Rightarrow$ Option C is correct.