SOLUTION: trains A & B are traveling in the same direction on parellel tracks. train a is traveling at 40 miles per hour and train b is traveling at 60 miles per hour. Trai na passes the sta

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Question 420918: trains A & B are traveling in the same direction on parellel tracks. train a is traveling at 40 miles per hour and train b is traveling at 60 miles per hour. Trai na passes the station at 3:10am. If train b passes the same station at 3:22am, at what time will train b catch up to train a.
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Start a stopwatch when train B leaves station at 3:22
How much of a head start does train A have?
Train A left 12 minutes earlier at 3:10, and at 40 mi/hr
d+=+40%2A%2812%2F60%29
d+=+40%2F5
d+=+8 mi is A's head start
Both trains will now run for the same amount of time,
but A has less distance to travel.
Let d = distance from station to where they meet
------------------
Train A:
(1) +d+-+8+=+40%2At+
Train B:
(2) d+=+60%2At+
-------------
(1) +d+=+40t+%2B+8+
(2) +d+=+60t+
+40t+%2B+8+=+60t+
+20t+=+8+
+t+=+2%2F5+ hrs
t+=+%282%2F5%29%2A60 min
+t+=+24+ min
This is 24 minutes after the stopwatch started at 3:22,
so B catches A at 3:46 AM