SOLUTION: Scott left the airport and traveled toward the train station at 20 mph. 3 hours later Jenny left the airport driving at 50 mph in an effort to catch up to Scott. How long did Jenny

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Question 925415: Scott left the airport and traveled toward the train station at 20 mph. 3 hours later Jenny left the airport driving at 50 mph in an effort to catch up to Scott. How long did Jenny have to drive to catch up to Scott?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Scott's head start = +20%2A3+=+60+ mi
Start a stopwatch when Jenny leaves
Stop the stopwatch at time +t+ in
hrs when she catches Scott
Let +d+ = distance in miles she travels
until she catches Scott
-------------------------
Scott's equation:
(1) +d+-+60+=+20t+
Jenny's equation:
(2) +d+=+50t+
-----------------
Substitute (2) into (1)
(1) +50t+-+60+=+20t+
(1) +30t+=+60+
(1) t = 2 }}}
Jenny catches Scott in 2 hrs
--------------------------
check:
(1) +d+-+60+=+20%2A2+
(1) +d+=+60+%2B+40+
(1) +d+=+100+
and
(2) +d+=+50%2A2+
(2) +d+=+100+