Question 104939: Brittani and Lea, two cyclists, start simultaneously. Brittani at point A and Lea at Point B. They travel toward each other at constant sppeds. They pass each other in 30 minutes, and Brittani, headed for point B, arrives there in another 20 minutes. How many minutes after brittani arrives at point B will Lea arrive at Point A?
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! Brittani and Lea, two cyclists, start simultaneously. Brittani at point A and Lea at Point B. They travel toward each other at constant speeds. They pass each other in 30 minutes, and Brittani, headed for point B, arrives there in another 20 minutes. How many minutes after Brittani arrives at point B will Lea arrive at Point A?
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We know that it took B 20 min to go the distance L required 30 min to go.
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We need to know how long it will take L the cover the distance that B covered in 30 min
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Let d1 = dist from B to where they met. Speed = Dist/time (in min)
B's speed = d1/20
L's speed = d1/30
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Find out the distance (d2) from A to where they met: Dist = speed * time
d2 =  * 30
d2 =  d1
d2 = 1.5*d1
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Find Time required for L to travel 1.5*d1: Time = dist/speed
L's time = 1.5d1/(d1/30)
L's time = 1.5d1 * 30/d1
L's time = 1.5 * 30; d1's cancel
L's time = 45 min
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It asked how long after B gets to pt B will L get to point A
It would be 45 - 20 = 25 minutes.
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Did this help, hope I made it understandable.
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