Question: Aaron and Vanessa were relay race partners on a running team. Aaron was able to run each mile twice as fast as Vanessa, but Vanessa was able to run twice as far as Aaron did. If Vanessa ran 4 miles and Aaron completed his part of the race in 16 minutes, how long in minutes did Vanessa take to complete her part?
How to solve this?
Answer: 
Vanessa ran twice as far as Aaron, so Aaron ran 4 / 2 = 2 miles.
Aaron took 16 minutes, so he ran each mile in 16 / 2 = 8 minutes.
Vanessa takes twice as long to run a mile, so she took 8 * 2 = 16 minutes for each mile.
She ran 4 miles, so she took 4 * 16 = 64 minutes to complete her part of the race.