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Percents Videos 20 videos
Looking to con someone out of 40% of a pizza? You've come to the right place. Just don't try that on us.
Converting percents to decimals is easy: just move the decimal point two to the left. Yep, that's it. To the left, to the left... convertin' th...
If the value of a painting increases by 15 percent every year, what was it worth 5 years ago? Hold up: why would you want to sell it now? In a few...
Converting Percents to Decimals 2408 Views
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Description:
Converting percents to decimals is easy: just move the decimal point two to the left. Yep, that's it. To the left, to the left... convertin' those decimals into percents .
Transcript
- 00:07
Converting Decimals, Percents, and Fractions, a la Shmoop.
- 00:11
You could think of decimals, percents, and fractions as three different languages for
- 00:15
numbers. Naturally, you sometimes need to translate
- 00:17
from one language to another. And lucky you, we’re here to help.
- 00:21
This is where conversion comes in. Conversion is the time-honored Western tradition
Full Transcript
- 00:26
of forcing others to believe exactly the same things that you do.
- 00:30
Actually, we’re talking about converting one “language” of a number into another.
- 00:35
For example, your “friend” got detention two out of five days this week.
- 00:39
That scenario could be expressed as a fraction. Or it could be expressed as a frantic exclamation,
- 00:45
as in: <<DS voice>> “My parents are going to kill me!”
- 00:49
Or we could turn it into a percentage, by calculating how many detentions your friend
- 00:53
is on pace for over the course of 100 days. Remember, percent really means “per hundred.”
- 01:00
Five times twenty equals one hundred, so we also multiply two times twenty, which equals
- 01:05
forty. Now we have forty over one hundred, or forty
- 01:09
percent. That 40% detention rate could also be expressed
- 01:12
as 40 point zero percent. When you start listing your detention percentage
- 01:17
with a decimal point, it may be a wake up call to get some help.
- 01:21
To convert forty percent into a decimal, we simply move the decimal point two places to
- 01:26
the left. This gives us the decimal zero point four.
- 01:29
Great batting average. So two-fifths equals forty percent equals
- 01:34
zero point four. Let’s try a quick drill.
- 01:37
What percent is zero point nine? Ninety percent. Good free throw percentage
- 01:42
for basketball. Bad survival rate for appendectomies. Now let’s turn it into a fraction.
- 01:48
Since percent means per hundred, we know ninety percent is really ninety out of one hundred.
- 01:53
We can reduce it to make everything nice and neat.
- 01:57
Ninety and one hundred can both be divided by ten, giving us nine-tenths.
- 02:02
Are you fluent in decimals, percents, and fractions yet?
- 02:04
Don’t worry if you’re only 50% of the way there.
- 02:16
In that case, you only have 60% more to go. Wait…
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