A car drives 60 miles on local roads at 30 mph, and 65 miles on the highway at 65 mph, what is the average speed of the entire trip?  Choose the correct choice from the following
A) 36 mph	B) 40 mph	C) 44 mph	D) 42 mph	E) 58 mph
So The Answer is Plainly D....   we have a general relation for speed , time and distance : v (velocity) * t ( time)= d (distance)   for first part we have d=60 miles , and v= 30 mph so we can obtain time : 30*t = 60 Or t= 60/30= 
<gadget id="calculator">60/30</gadget>
<output>2</output>
2 hours the needed time to cover 60 miles   in the same way we should divide 65 by 65 to find the needed time to cover 65 miles ,so t= 1 hours   so the total time for covering total distance would be  2+1= 
<gadget id="calculator"> 2+1</gadget>
<output>3</output>
3 hours and total distance is   60+65= 
<gadget id="calculator">  60+65</gadget>
<output>125</output>
125 miles   Final stage : average speed is total distance divide to total time : 125/3= 41.6 miles per hour that rounds up to 42....
<result>D</result>
A car drives 60 miles on local roads at 30 mph, and 65 miles on the highway at 65 mph, what is the average speed of the entire trip?