Problema Solution

bill drives 120 miles from his house in san diego to los angeles for a business meeting. Afterward, he drives from la to las vegas, a distance of 240 miles. if he averages the same speed on both legs of the trip and it takes him 2 hours less to go from san diego to los angeles, what is his average driving speed?

Answer provided by our tutors

let the speed from la to lv = t hrs

distance between s to la is 120 miles

distance between la to lv is 240 miles

now according to question 

120/t-2  = 240/t

t = 2t -4

t = 4 hrs

now av.speed = 240 /t = 120/t-2 = 120/4-2 = 120/2 = 60miles/hr