Myra drove at an average speed of 30 miles per hour for T hours and then at an average speed of 60 miles/hr for the next T hours. If she made no stops during the trip and reached her destination in 2T hours, what was her average speed in miles per hour for the entire trip?
Pick.
A) The average speed is 40 miles per hour.
B) The average speed is 45 miles per hour.
C) The average speed is 48 miles per hour.
D) The average speed is 50 miles per hour.
E) The average speed is 55 miles per hour.
Here, time for which Myra traveled at the two speeds is same.   Average Speed = (a + b)/2 = (30 + 60)/2= 
<gadget id="calculator">(30 + 60)/2</gadget>
<output>45</output>
45 miles per hour   Answer (The average speed is 45 miles per hour.)
<result>B</result>
Myra drove at an average speed of 30 miles per hour for T hours and then at an average speed of 60 miles/hr for the next T hours. If she made no stops during the trip and reached her destination in 2T hours, what was her average speed in miles per hour for the entire trip?