ShmoopTube

00:03

Here's an unshmoopy question you'll find on an exam somewhere in life...

00:06

The following graph shows the number of minutes that Kate had spent working on

00:10

math homework over the course of a week.

00:13

Which day had the greatest percentage increase in time spent from the previous day? 

00:18

Here are the potential answers:

00:25

Okay, so this question is testing whether we can read a graph...

00:30

...and do we know what percentage increase means? Well, let's see.

00:34

Percentage change is calculated by taking the new number minus the original number

00:38

divided by the original number. New minus old over old. Remember that mantra.

00:43

In this case, percentage increase means that the new number must be larger than the original number.

00:51

So, just by looking at the graph, we can see that Friday and Saturday are decreases.

00:55

So we can automatically eliminate choice D.

00:58

Taking a look at our other answer choices, Tuesday, Wednesday, and Friday...

01:03

as in any percent question, a little red light should go off in our head,

01:06

indicating that things off of a small base can grow a lot

01:11

in the next iteration simply because the base is so small.

01:15

We don't actually have the calculate the percentages.

01:17

That would be a pain and a waste of time.

01:20

If we just do a visual inspection of the graph, we can see that the increase from Thursday to Friday is the largest.

01:27

So our answer is C, Friday.

01:29

...which, if you ask us, is a weird night to do the majority of your homework.

01:33

Take a night off, Kate. You've earned it.

01:36

Just don't party too hard.

Full Transcript