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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.
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.
Full Transcript
- 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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