A train traveled the first d miles of its journey it an average speed of 50 miles per hour, the next d miles of its journey at an average speed of y miles per hour, and the final d miles of its journey at an average speed of 160 miles per hour. If the train’s average speed over the total distance was 96 miles per hour, what is the value of y?	Answers.
A) 68
B) 84
C) 90
D) 120
E) 160
Average speed=Total distance traveled /Total time taken   3d/d/50+d/y+d/160=96   Solving for d and y,   15y=11y+480   3y=480   y=160   Answer 160
<result>E</result>
A train traveled the first d miles of its journey it an average speed of 50 miles per hour, the next d miles of its journey at an average speed of y miles per hour, and the final d miles of its journey at an average speed of 160 miles per hour. If the train’s average speed over the total distance was 96 miles per hour, what is the value of y?