Problema Solution
Ellen drove 1.8 hours on Friday, Saturday night her trip back took 2 hours. Her average speed on Saturday was 4 mph slower than Friday. What was her average speed.
Answer provided by our tutors
Let 'v' represent Ellen's average speed on Saturday then her average speed on Friday was 'v + 4'.
Since distance = speed*time we have:
1.8(v + 4) = 2v
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click here to see the equation solved for v
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v = 35 mph
35 mph was Ellen's average speed on Saturday.
35 + 4 = 39 mph was Ellen's average speed on Friday.