ShmoopTube

00:03

Here's a shmoopy question for you...

00:06

Two trolls, Jimmy and Jonny, are walking home after a long night of...clubbing.

00:11

Their distances from home (in feet) as a function of time (in seconds) are given by the following graph.

00:20

After 10 minutes of walking, how far apart are they?

00:23

Here are the potential answers...

00:25

Before we spoil the ending, hit pause and try it yourself.

00:30

Can we read a graph? Answer: yes.

00:33

Can we read it accurately? Eih...well, let's see.

00:37

OK so the first prep work we have to do here is to get the units all on the same page.

00:42

The trolls are walking...well, lumbering, really...

00:49

10 MINUTES, and the graph is giving us the time units in seconds. Thanks a lot, graph.

00:54

So...with 60 seconds in a minute, and 10 minutes involved,

00:58

we need the mark to hit at the 600 point.

01:02

Now draw a line vertically from that point and let's see where it intersects.

01:05

Looks like about...here.

01:07

In 10 minutes, Jimmy walked this many feet;

01:10

and in those same 10 minutes, Jonny walked this many feet.

01:14

We have to label a few grid lines here.

01:17

This one is half way between 4800 and 2400 so it's gotta be 3600...

01:21

...this line is half way between 3600 and 2400 so it's gotta be 3000...

01:27

...and this one is half way between 3600 and 4800 so it's gotta be 4200.

01:33

So now we just note the feet.

01:35

Jimmy is 3000 feet along the way and Jonny is 3600 feet along the way...

01:41

so they are 3600 minus 3000 feet...or 600 feet apart.

01:46

And the answer is B.

01:47

See, that wasn't too ogre-ly complicated!

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