Harry Rosenfeld (editor for local news): Woodward. Bernstein. You're both on the story. Now don't f**k it up.
How to follow a unit
Challenge Problem 1
Your average driver in a congested parking garage drives at about 4.5 miles per hour. What is that in feet per minute?
(useful info: 1 mile = 5280 feet)
Before we actually get to the problem, I want to talk about multiplying fractions (see, just like Deep Throat - start off with seemingly unrelated topics - don't worry, it will all come together, and soon).
You undoubtedly know that when you multiply any fraction by 1, you get the same number. We can do this in a boring way:
... and 9/2 is the same as 4.5, of course.
Or in a fancy but not terribly useful way:
... which is, again, the same as 4.5, since 5490/1220 = 4.5
(That's the date of the latest Mayan apocalypse, for those of you with sharp eyes).
Or, you can multiply by one in a fancy and spectacularly useful way:
which is the same as...
Be careful... 4.5 = 23760? Clearly not. Here's where you need to pay attention to the units. The correct thing to do is to cancel out the "miles", which leaves:
4.5 miles = 23760 feet.
That's following the units.
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