Two boats are heading towards each other at constant speeds of 4 miles/hr and 20 miles/hr respectively. They begin at a distance 20 miles from each other. How far are they (in miles) one minute before they collide ?	Choose the correct choice from the following answers
A) 1/12  B) 6/15  C) 1/6  D) 1/3  E) 1/5
The question asks: how far apart will they be 1 minute=1/60 hours before they collide?   Since the combined rate of the boats is 4+20=25 mph then 1/60 hours before they collide they'll be rate*time=distance --&gt; 24*1/60=6/15miles apart.   Answer: 6/15.
<result>B</result>
Two boats are heading towards each other at constant speeds of 4 miles/hr and 20 miles/hr respectively. They begin at a distance 20 miles from each other. How far are they (in miles) one minute before they collide ?