SOLUTION: a bus must travel 45 miles per hour to make its 6 hour trip on time. during the first hour, the bus had to slow to 25 miles per hour because of snow. what should its average speed

Algebra ->  Human-and-algebraic-language -> SOLUTION: a bus must travel 45 miles per hour to make its 6 hour trip on time. during the first hour, the bus had to slow to 25 miles per hour because of snow. what should its average speed       Log On


   



Question 908453: a bus must travel 45 miles per hour to make its 6 hour trip on time. during the first hour, the bus had to slow to 25 miles per hour because of snow. what should its average speed be for the rest of the trip to be on time?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
A +6+ hr trip at +45+ mi/hr means:
+d%5B1%5D+=+45%2A6+
+d%5B1%5D+=+270+ mi
is the distance of the entire trip
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For the 1st hr,
+d%5B2%5D+=+25%2A1+
+d%5B2%5D+=+25+ mi
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+270+-+25+=+245+ mi
is the distance left to travel
after the 1st hr
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Let +s+ = speed needed to make
the entire trip ion +6+ hrs
There is +6+-+1+=+5+ hrs left
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+245+=+s%2A5+
+s+=+245%2F5+
+s+=+49+
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The average speed should be 49 mi/hr
for the last 5 hrs
to make the trip on time