math
posted by tiger on .
harry drove for 4 hours on the freeway , he decreased his speed by 20 mph than drove for 5 hours on the country road. If his total trip was 449 miles, than what was his speed on the freeway

distance = speed * time, so if his freeway speed was s, then
4s + 5(s20) = 449 
Freeway speed
Country road speed
4r + 5(r20) =449
4r +5r 100 =449
9r = 549
r = 61
Freeway 61 mph 
Harry drove for 3 hours on the freeway, then decreased his speed by 20 miles per hour and drove for 6 more hours on a county road. If his total trip was 330 miles, than what was his speed on the freeway?