John traveled 80% of the way from Yellow-town to Green-fields by train at an average speed of 80 miles per hour. The rest of the way John traveled by car at an average speed of v miles per hour. If the average speed for the entire trip was 55 miles per hour, what is v in miles per hour? Select
A) 30 B) 40 C) 50 D) 55 E) 70
HiBunuel   THe question seems incorrect. it should not be 80% at the speed of 80. However if it's 20% at the speed of 80, Answer comes out 55.   The question is correct. Here's the explanation:   Let distance be D. We can find the total timeequate it, which comes as:   0.8D / 80 + 0.2D / v = D / 55 =&gt; v = 50 (Option 50).
<result>C</result>
John traveled 80% of the way from Yellow-town to Green-fields by train at an average speed of 80 miles per hour. The rest of the way John traveled by car at an average speed of v miles per hour. If the average speed for the entire trip was 55 miles per hour, what is v in miles per hour?