Question

Pamela drove her car 99 kilometers and used 9 liters of fuel. She wants to know how many kilometers, (k), she can drive with 12 liters of fuel. She assumes the relationship between kilometers and fuel is proportional. How many kilometers can Pamela drive with 12 liters of fuel?

Answer 1

99 km ... 9 liters
x km   ... 12 liters

If the relationship is proportional, we have

$\frac{99}{x} = \frac{9}{12}$

from where 

$x = \frac{99*12}{9}= \frac{1188}{9}=\bold{132}$

The answer is 132 kilometers.