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Hint for Problem 9

Let's say I drive up to Magic Mountain next month to ride some roller coasters.
It's roughly 180 miles away up north of LA, for those who don't know. If I
drive a nice steady 60 mph, how long would it take me to get there?
The relationship between distance, speed, and time is given by

distance = time × speed (1)
or

*d = t s* (2)
From Equation 2, you will probably see that you can answer
my question easily. Since *d* = *t s*, all you have to do is divide
the distance (180 miles) by the speed (60 miles/hour), and you get the time,
which in my case is 3 hours.

You may have also noticed that Equation 2 looks just like
the equation for a straight line:

*y = m x* (3)
(compare Equations 2 and 3). That
means that if you plot a graph with distance on the Y-axis and speed on the
X-axis, you will get a straight line whose slope has the units of time (years,
seconds, etc.).

Greg Anderson

anderson@python.ucsd.edu

Tue Jan 6 17:28:15 PST 1998