John and Amanda stand at opposite ends of a straight road and start running towards each other at the same moment. Their rates are randomly selected in advance so that John runs at a constant rate of 3, 4, or 5 miles per hour and Amanda runs at a constant rate of 4, 5, 6, or 7 miles per hour. What is the probability that John has traveled farther than Amanda by the time they meet?
Choices.
A) 1/16	B) 1/12	C) 1/8	D) 1/6	E) 1/3
John will run farther if he runs at 5 mph and Amanda runs at 4 mph.   P(John runs farther) = 1/3 * 1/4 = 1/12   The answer is 1/12.
<result>B</result>
John and Amanda stand at opposite ends of a straight road and start running towards each other at the same moment. Their rates are randomly selected in advance so that John runs at a constant rate of 3, 4, or 5 miles per hour and Amanda runs at a constant rate of 4, 5, 6, or 7 miles per hour. What is the probability that John has traveled farther than Amanda by the time they meet?