SOLUTION: Malik drove his car for 45 miles at an average speed of r miles per hour. On the return trip, traffic has increased, and Malik's average speed in 3/4r. The round trip took a tota

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: Malik drove his car for 45 miles at an average speed of r miles per hour. On the return trip, traffic has increased, and Malik's average speed in 3/4r. The round trip took a tota      Log On

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Question 736465: Malik drove his car for 45 miles at an average speed of r miles per hour. On the return trip, traffic has increased, and Malik's average speed in 3/4r. The round trip took a total of 1 hour and 45 minutes. Find the average speed for each portion of the trip.
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The time for the 1st portion was +45%2Fr+
The time for the 2nd portion was +45%2F%28%28+3%2F4%29%2Ar%29+=+60%2Fr+
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+1.75+=+45%2Fr+%2B+60%2Fr+
+1.75r+=+45+%2B+60+
+1.75r+=+105+
+r+=+60+
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Ave speed for 1st part: +r+=+60+ mi/hr
Ave speed for 2nd part: +%283%2F4%29%2Ar+=+45+ mi/hr