SOLUTION: A Piper Saratoga airplane leaves Philadelphia at noon, and flies in a straight line toward Pittsburgh at a constant 150 mph. One hour later, a Piper 6X plane leaves Pittsburgh

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Question 833843: A Piper Saratoga airplane leaves Philadelphia at noon, and flies in a
straight line toward Pittsburgh at a constant 150 mph. One hour later, a
Piper 6X plane leaves Pittsburgh and flies in a straight line toward
Philadelphia at a constant 120 mph. The distance between Philadelphia
and Pittsburgh is 310 miles.

a. Calculate the time on a passenger's watch when the two planes pass
each other.

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Say the Piper Saratoga =PS
Say the Piper 6X =6X
--------------------
How far does PS fly in 1 hr?
+d%5BPS%5D+=+150%2A1+
+d%5BPS%5D+=+150+ mi
-------------------
The distance between them is now
+310+-+150+=+160+ mi
Let +d+ = the distance PS travels
until they pass each other
+160+-+d+ = distance 6X travels until they
pass each other
Let +t+ = the time in hours from when
6X leaves Pittsburg until the pass each other
--------------------
PS equation:
(1) +d+=+150t+
6X equation:
(2) +160+-+d+=+120t+
----------------------
Substitute (1) into (2)
(2) +160+-+150t+=+120t+
(2) +270t+=+160+
(2) +t+=+.5926+ hrs
+.5926%2A60+=+35.555+
+.555%2A60+=+33.333+
-----------------------
In minutes, +t+ = 35 min 33 sec
This is the time after 1 PM, so the time
on a passenger's watch when they pass is
1:35:33 PM
---------------
Check answer:
(1) +d+=+150t+
(1) +d+=+150%2A.5926+
(1) +d+=+88.889+
and
(2) +160+-+d+=+120t+
(2) +160+-+d+=+120%2A.5926+
(2) +d+=+160+-+71.111+
(2) +d+=+88.889+
OK