Question

Steve traveled 200 miles at a certain speed. Had he gone 10mph faster, the trip would have taken 1 hour less. Find the speed of his vehicle

Answer 1

Distance = Rate x Time
Distance is equal in each case 200 miles.
D = RT = (R+10) x (T-1)

Answer is in case 1 the car is driving 5 hours at 40 mph
In case 2 -- the car is going 10 mph greater which is 50 mph, and gets there in 4 hours

5hrs x 40 mph = 200 miles 4 hrs x 50 mph = 200 miles

Answer 2

similar to the above.
as the distance travelled is thte same,
(s+10)(t-1) = st
10t-s-10 =0
10t-s=10 ---(1)
since s=d/t, t=200/s --(2)
Sub(2) into (1)
10(200/s) -s =10
s^2 +10s - 2000 =0
s=40mph or s=-50mph (rejected)
therefore, speed required is 40 mph

Answer 3

thank you