SOLUTION: Suppose a car moving at a constant speed travels 96 miles. If the car's speed was twelve miles per hour faster, it could have traveled 120 miles in the same amount of time. What wa

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Question 957848: Suppose a car moving at a constant speed travels 96 miles. If the car's speed was twelve miles per hour faster, it could have traveled 120 miles in the same amount of time. What was the car's speed (in miles per hour)? Type in your numerical answer only; do not type any words or letters with your answer.

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +s+ = the car's actual speed in mi/hr
Let +t+ = the car's time in both cases
-------------------
1st case:
(1) +96+=+s%2At+
2nd case:
(2) +120+=+%28+s+%2B+12+%29%2At+
------------------------
(1) +s+=+96%2Ft+
(2) +120+=+s%2At+%2B+12t+
By substitution:
(2) +120+=+%28+96%2Ft+%29%2At+%2B+12t+
(2) +120+=+96+%2B+12t+
(2) +12t+=+24+
(2) +t+=+2+ hrs
------------------
(1) +s+=+96%2Ft+
(1) +s+=+48+
The car's actual speed was 48 mi/hr