Gill drives 120 miles from Los Angeles to San Diego to fetch a package. On her way there she drives at 40 miles per hour. On her way back she drives 50% faster. What is Gill's average velocity R for the round trip?
Choose the correct option.
A) 24 miles per hour B) 48 miles per hour C) 50 miles per hour D) 53 1/3 miles per hour E) 68 miles per hour
Here's an Average Speed question in which the prompt gives you almost all of the immediate numbers needed to work with.   Driving from LA to SD, we have a distance of 120 miles and a speed of 40 miles/hour.   D = (R)(T)   120 = (40)(T)   120/40= 
<gadget id="calculator">120/40</gadget>
<output>3</output>
3= T   3 hours to drive to SD   On the way back, she drives 50% FASTER. Gill's return speed is (1.5)(40) = 60 miles/hour.   D = (R)(T)   120 = (60)(T)   120/60= 
<gadget id="calculator">120/60</gadget>
<output>2</output>
2= T   2 hours to drive to SD   Total Distance = 240 miles   Total Time = 3+2= 
<gadget id="calculator">3+2</gadget>
<output>5</output>
5 hours   Average Speed= 240/5= 
<gadget id="calculator">240/5</gadget>
<output>48</output>
48 miles/hour   Final Answer:   48 miles per hour
<result>B</result>
Gill drives 120 miles from Los Angeles to San Diego to fetch a package. On her way there she drives at 40 miles per hour. On her way back she drives 50% faster. What is Gill's average velocity R for the round trip?