Question 560312: I need help with this word problem. i have to use a formula d=r*t and i also draw a table to find what the equation will look like
Problem:
At 10 a.m. Dana leaves for work riding her motorbike at 30 mph. Her husband Bill, realizes that she left some important papers and so he leaves 20 minutes later to deliver the papers. if he drives the same route at 50 mph, how long will it take him to catch up to her?
my table i set up
d = r * t
Dana d=10(r-30) r-30 10
Bill d=20r r 20
20r=10(r-30)
20r=10r-300
-10r=-10r
10r/10= -300/10
r=-30
is this right and if it is where do i go from here?
Answer by josmiceli(19441)   (Show Source):
You can put this solution on YOUR website! I can solve it the way I do this kind of problem
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I imagine that a stopwatch is started when the
2nd person, Bill, leaves. Then I need to know
how much of a head start the 1st person, Dana, got.
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Dana's head start is
 ( note that 20 min is 1/3 of an hour )
 mi
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Now when the stopwatch is started, they both will be
traveling for the same amount of time,  , until they meet
Let  = distance Bill travels in this time
Bill's equation:
(1) 
Dana's equation:
(2)  ( Dana has 10 mi less to travel )
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Substitute (1) into (2)
(2) 
(2) 
(2) 
It will take him a half hour to catch her
check answer:
(1)
(1) 
(1) 
and
(2)
(2) 
(2) 
(2)
This is the distance from home to where they meet
OK
The table would have  , their speeds, t, and
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