Problema Solution
Harry drove for 6
hours on the freeway, then decreased his speed by 20 miles per hour and drove for 6
more hours on a country road. If his total trip was 564
miles, then what was his speed on the freeway?
Answer provided by our tutors
Let
v = the speed on the freeway
t1 = 6 hr the time of the travel with speed v
v - 20 = the decreased speed on the country road
t2 = 6 hr the time of the travel with speed v - 20
d = 564 mi the distance traveled
Since distance = speed*time we have:
vt1 + (v - 20)t2 = d
6v + 6(v - 20) = 564
........
click here to see the equation solved for v
........
v = 57 mph
Harry's speed on the freeway was 57 mph.