SOLUTION: Steve traveled 600 miles at a certain speed. Had he gone 20mph faster, the trip would have taken 1 hour less. Find the speed of his vehicle.
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-> SOLUTION: Steve traveled 600 miles at a certain speed. Had he gone 20mph faster, the trip would have taken 1 hour less. Find the speed of his vehicle.
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Question 84758: Steve traveled 600 miles at a certain speed. Had he gone 20mph faster, the trip would have taken 1 hour less. Find the speed of his vehicle.
You can put this solution on YOUR website! We know that distance = speed * time. Now Let us denote the speed by s and speed by t then
600= s * t
where s is in miles per hour and t is in hours
Now Second condition says that had he gone 20mph faster, the trip would have taken 1 hour less. But the distance remains the same
so
in the second case:
600=(s+20)(t-1)
which means if we equate the two equations, we have
st= (s+20)(t-1)
solving:
s= 20t -20
substituting the value of t from the equation 600 = st in terms of s, we have
which yields to
solving by quadratic equation method and taking the positive value only, we have
s=100 miles per hour
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