SOLUTION: When driving 18 miles, how much time would you save if you drove 60 mph instead of 55 mph? And what is the equation for this problem?

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Question 759959: When driving 18 miles, how much time would you save if you drove 60 mph instead of 55 mph? And what is the equation for this problem?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +t%5B1%5D+ = time when driving at 60 mi/hr
Let +t%5B2%5D+ = time when driving at 55 mi/hr
Driving at 60 mi/hr:
+18+=+60t%5B1%5D+
+t%5B1%5D+=+.3+
Driving at 55 mi/hr:
+18+=+55t%5B2%5D+
+t%5B2%5D+=+.3273+
+t%5B2%5D+-+t%5B1%5D+=+.3273+-+.3+
+t%5B2%5D+-+t%5B1%5D+=+.0273+
+.0273%2A60+=+1.636+
+.636%2A60+=+38+
By driving 18 mi at 60 instead of 55, you save
1 min 38 sec