#### Answer

$16 \text{ billion}\text{ km}\approx 9.942\text{ billion mi}$

#### Work Step by Step

If want to convert from kilometers to miles, we have to consider the following conversion rate:
$1.6093\text{ km}\approx 1 \text{ mi}$
By dividing both sides by $1.6093$, we get:
$1\text{ km}\approx \frac{1}{1.6093} \text{ mi}$
We multiply both sides by $16 \text{ billion}$ in order to get the answer to the question:
$16 \text{ billion}\text{ km}\approx \frac{16 \text{ billion}}{1.6093} \text{ mi}=\frac{16}{1.6093} \text{ billion mi}\approx 9.942\text{ billion mi}$