ShmoopTube

Where Monty Python meets your 10th grade teacher.

Search Thousands of Shmoop Videos

Percents of Change 7413 Views


Share It!


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…

Up Next

SAT Math 10.3 Geometry and Measurement
3336 Views

SAT Math 10.3 Geometry and Measurement. What is the ratio of birds to dogs?

Related Videos

SAT Math 2.1 Statistics and Probability
343 Views

SAT Math 2.1 Statistics and Probability. Which two items have the highest protein to fat ratio?

SAT Math 2.2 Statistics and Probability
242 Views

SAT Math 2.2 Statistics and Probability. What percent of her recommended daily intake of 2000 calories did she consume?

SAT Math 4.2 Statistics and Probability
234 Views

SAT Math 4.2 Statistics and Probability

SAT Math 4.4 Geometry and Measurement
210 Views

SAT Math 4.4 Geometry and Measurement