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Percents of Change 7413 Views


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Description:

This video covers how to calculate percents of change by demonstrating how to calculate a price change. Just divide the price decrease by the original price, then convert the number to a percent by moving the decimal point.

Language:
English Language
Common Core Standards:

Transcript

00:04

Percents of Change, a la Shmoop. There’s nothing Larry the Lobster loves

00:08

more than playing his LBox after a long day of...wait, what is it lobsters do?

00:14

That’s it, a long day of lobotomies. However, the new LBox controller has too many

00:22

buttons…

00:22

… and Larry needs to buy the retro model again.

00:25

Because Larry is a lobster. When the LBox was first introduced a few years

00:30

ago it was $249.

00:32

But by now the price has been slashed to $199.

00:37

What is the percent of the decrease? To find the formula we will use to solve the

00:41

problem, let’s ask ourselves what we’re looking for.

00:43

We know the reduced price, which we call the “price decrease…”

00:47

…and we want to know what percent of the original price that is, which we call the

00:53

“percent decrease.”

00:54

To find the The Percent Decrease we will need to divide the Price Decrease by the Original

00:59

Price. First, let’s find the Price Decrease, which

01:02

is the Original Price minus the Discounted Price.

01:06

249 minus 199 equals 50. Now let’s plug in the numbers we know.

01:14

Price Decrease is 50, and Original Price is 249. So, this gives us our formula: Percent

01:20

decrease = 50 divided by 249.

01:25

That gives us point-201. But we are looking for a percent.

01:29

To convert it to a percent, just move the decimal point over two places to the right.

01:34

So the percent decrease equals 20.1 percent. Awesome! Despite Larry’s lack of opposable

01:39

thumbs, he can finally claw his way to beating The Legend of Zelda.

01:43

Larry’s math skills will be just fine, but we’re still concerned about how he makes

02:06

a living…

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