Susan drove an average speed of 15 miles per hour for the first 40 miles of a tripthen at a average speed of 60 miles/hr for the remaining 20 miles of the trip if she made no stops during the trip what was susan's avg speed in miles/hr for the entire trip
Choose the correct choice from the following answers
A) 35	B) 20	C) 45	D) 50	E) 55
Avg. speed = total distance / total time   Total distance = 60 miles   Total time = 40 / 15 + 20/60= 
<gadget id="calculator">40 / 15 + 20/60</gadget>
<output>3</output>
3   Avg. speed= 20.   Answer - 20
<result>B</result>
Susan drove an average speed of 15 miles per hour for the first 40 miles of a tripthen at a average speed of 60 miles/hr for the remaining 20 miles of the trip if she made no stops during the trip what was susan's avg speed in miles/hr for the entire trip