Question

If one airplane can travel at max speed of $600$ miles per hour and the another airplane at max speed of $720$ miles per hour, then how many more miles can the faster airplane travel in $12$ seconds than the slower airplane?

• A. $\frac{1}{30}$
• B. $\frac{2}{5}$
• C. $2$
• D. $30$

Answer 1

The correct option is B $\frac{2}{5}$

First convert miles per hour to miles per second.
Slower airplane speed $=600$ miles per hour
$\frac{600}{3600}\times 12=2$ miles
Faster airplane speed $=720$ miles per hour
$\frac{720}{3600}\times 12=2.4$ miles
The faster plane can travel $2.4-2=0.4$ miles farther, which is the same as $\frac{2}{5}$