Up next in 10
We've already learned how to express fractions as percents and vice versa. Now we'll learn how to express percents as decimals and decimals as percents. We'll also learn how to compare and order fractions, decimals and percents.
Chapters:
00:00 Introduction
00:18 Percent To Decimal
02:39 Decimal To Percent
04:03 Working on several examples
06:51 Fraction to Percent
09:51 Real life example
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0:00
so we're talking fractions that's most
0:01
in percent
0:03
right first we're going to learn how to
0:05
go from what
0:10
rock we going to learn how to go from
0:12
percentage to decimals that's easy very
0:15
easy stuff right
0:18
again to write a percent as a decimal
0:21
you just divide it by 100 and do what
0:24
and then remove the symbol right so if
0:27
you want to go for example 16% you just
0:30
have to divide by 100 16 over 100 and
0:32
just move take away the symbol right and
0:35
then how do you know when you divide by
0:37
100 what do you do when you divide
0:38
number by 100 you move the decimal how
0:39
many places to the right one two two
0:42
places to the right every time you
0:44
divide by 100 that means you move the
0:46
decimal two places to the right right
0:48
and then if you go from a percentage to
0:50
a decimal you have to remove the symbol
0:52
16% is the equivalent of what is the
0:55
equivalent of
0:56
0.16 right it's the same thing again
0:58
this is one of the easiest things
1:00
and you can use your calculator you
1:02
should use your calculator right it's
1:04
easy stuff right so again if I have 16%
1:08
I just write it as 16 over 100 and
1:11
that's 0.16 if it's
1:14
7% why would I be equal to 0.7 plus 7
1:18
over what 100 is it 0.7 or 0.07 0. 0.07
1:23
because if you start here I'm going to
1:25
move it right actually I say the damage
1:28
thing you don't move the decimal to the
1:30
right but to the left two places to the
1:32
left all right so if you were watching
1:34
the video I'm sorry so it's two places
1:36
to the left so we're going to start from
1:38
here right we're going to go one and two
1:40
so it's going to be 0.07 so this is
1:43
0.07 and then we make sure we take away
1:46
the percent symbol right now what if I
1:49
had
1:50
0.2% how would I write that as a
1:52
fraction
1:54
anybody
1:57
0.2% how do I go from that to a decimal
1:59
first I need to turn into a fraction yes
2:02
so you move the
2:05
decimales to the left right so if I
2:08
start here 0.2 I'm going to go what I'm
2:10
going to go from here I'm going to go
2:12
one and another one and I put a dot here
2:15
so
2:16
0.02 right this is what it is 0.02 so
2:20
you have to be very careful when you
2:21
when you do these things all right so
2:23
that's just pretty much from go going
2:25
from percent to decimal so now how do
2:27
you go from decimal to percent right
2:30
again you doing you going the backward
2:33
right if you can go forward you can also
2:35
go backward right you can you can figure
2:37
it out so to write a decimal as a
2:39
percent you multiply by what by 100
2:42
right to go from percent to decimal you
2:44
divide by 100 but to go from deal to
2:47
perc you do what you multiply by 100 and
2:51
add what the percent symbol right for
2:54
example
2:55
0.7 and I want to turn this into a
2:57
percentage I'm going to do what I'm
2:58
going to do 0.7 times 100 and that turns
3:02
into what 70 I have to make sure I put
3:05
the symbol right so example if I give
3:07
you a homework you go 0.70 70 that's
3:10
false it's not 70 it's
3:12
70% right we need to understand the
3:14
proper language the proper way of
3:17
interpreting things we can't just put
3:19
seven I no the Sy matters a lot because
3:22
it says that this is 70 over 100 does
3:25
that make sense right for example 0.03 I
3:29
said percentage you're going to do 0.03
3:32
* what * 100 and that gives you what
3:36
3% right so pretty simple stuff so
3:39
chapter 6 and 7 should be our go-to
3:42
chapters to kind of boost our grades up
3:44
it's really easy stuff right now let's
3:46
do some example here I want to turn 0.7%
3:49
as a fraction as a um as a percent what
3:52
would it be you open say yes this looks
3:56
really heavy as a fraction 0
4:03
i%% you% though
4:06
0.7% no no no no
4:09
0.7 I want to turn this into a actually
4:13
yeah you know what it's just a bunch of
4:14
different things here wait yeah we're
4:16
going to do look I have a list here 0.7%
4:19
as a decimal what would that be uh
4:23
0.7
4:26
0.07 right two what you from here you
4:30
moved it how many times two places to
4:32
the left right cuz it's 0.7% you divide
4:35
it by 100 if you're confused just divide
4:38
it by 100 sorry I didn't get that
4:41
right if you're confused just divide it
4:44
by 100 so what about 5% what would I be
4:48
shut up Siri what would it
4:53
be 5.37 right you see 537 is 5.37
5:00
because again we're dividing by 100 or
5:02
we just moving the decimal two places
5:04
for the left what about
5:08
12626 1.26 this should be the easiest
5:11
chapter what about
5:14
0.9%
5:16
99 right now I want to turn 0.09 into
5:23
percentage I get that I'm going to start
5:28
saying hey hey
5:31
stop yeah what that
5:33
be
5:35
again say 90% how is that
5:39
9%
5:42
0.01 no what would I be then 1% 1% right
5:47
1% what about
5:50
3.84
5:52
384
5:53
34% right because you again you multiply
5:56
by 100 Now what is 0.002
6:02
.2 0. 0.2% right make sure you put a
6:06
percentage symol what about
6:09
3106
6:11
31.6 31.6 so again this is probably one
6:15
of the funnest CHS to work with yeah so
6:18
it's basically always
6:22
say decimal ones or the way to think
6:25
about it for decimals is uh percent is
6:28
always just place in the decimal that's
6:31
right compare it to that that's right
6:33
yeah just like that right so if I'm I'm
6:36
decimal to% I'm going to the right I'm
6:39
moving forward right I'm going to move
6:40
it two places to the right that's 1% so
6:43
percentage to symbol I do what divide by
6:45
100 moov it to the left it's just that
6:47
right now we have now we going to go
6:49
from fraction to percent right we did
6:52
that last week from fraction to percent
6:54
so what do we do what was the key to
6:57
solving this how do I go from a fraction
6:58
to a percent
7:00
yeah compare it to X over 100 compare to
7:03
X over 100 because I want to get it over
7:05
100 right X over 100 now for some
7:07
fraction they are easier like I know I
7:09
can go from so what I do here if I had
7:12
like five I just have to multiply by 20
7:14
right but if I don't have like a number
7:15
that so obvious I I'm going to use this
7:18
here I'm going to set it to equal to X
7:20
over 100 because we want to know what 58
7:23
is in terms of a number over 100 right
7:26
and then we use what the cross
7:28
multiplication right again that's just a
7:31
preview of the test so this is 500 right
7:34
equal to
7:35
8X because I'm going like this right and
7:38
to find it I'm going to divide it by
7:40
what eight that gives you what then put
7:43
it in your
7:48
calculator what you get 62.5 who say
7:52
that so
7:54
62.5% right now am I am I going to write
7:57
62.5 or 62.5
8:00
% percent because I'm going to go from a
8:03
fraction to percentage so 62.5 I do not
8:06
forget to put my symbol because if I
8:08
don't put it that means I have totally
8:10
different things but I want to I want to
8:12
express it as a percentage so X is what
8:15
62.5 so the fraction is
8:18
62.5% right because if I just write 62.5
8:21
doesn't even make any sense because a
8:23
number of eight five over eight cannot
8:26
give you a number that's higher than one
8:28
right so this has to be a percent now 7
8:31
13 how do I turn this into a
8:35
percent equals to
8:37
what same same process right and we're
8:40
going to use again the cross
8:42
multiplication so we have 700 =
8:51
13x and then divide by 13 that gives us
8:57
what and then for this kind of questions
9:00
always go two places to the right right
9:03
run it to 100 every every time if I
9:05
don't specify so that's what I'm
9:07
expecting so what did you get for
9:10
this
9:13
535 53 what 85 all right
9:18
53.85% all right so
9:21
53.85% all right so now with this so now
9:24
we're going to try to work on a real
9:25
world problem right in an online survey
9:28
one f of teenagers say that their
9:32
favorite way of communicating with
9:34
friends is by email and then 21%
9:37
preferred text and 0.15 favor
9:43
in now the
9:45
question hey that's besides the point
9:49
let's let's work on this problem right
9:52
so we have one faith of teenagers say
9:54
that their favorite way of communicating
9:56
is by email 21%
9:59
text and 0.15 favor instant messaging
10:02
which is probably one of those right uh
10:06
maybe uh Snapchat or whatever you call
10:09
it which group of these is the
10:15
largest so how do we know which one is
10:17
the largest so first we need to find out
10:19
how many groups we have so first we have
10:23
the email what is the email what's the
10:26
fraction for the email
10:30
right so email is 1 what is the text
10:34
text is
10:35
what text is 21% right and then the last
10:40
one is group uh instant messaging right
10:42
that's 0.15 instant message I put I am
10:45
right now how would you compare these
10:47
numbers M it could be like maybe
10:52
Facebook Messenger
10:59
what I'll put them all as percent
11:01
because I know I can turn 0 into 15% and
11:05
and I know 1.5 is the easy way to that's
11:09
right right so to do this it's better to
11:12
have everything in percentage here right
11:14
so we already have the tax Mage 21% so
11:16
we can turn 0.15 to a percentage what
11:18
would that be 15 15% we just have to
11:21
move in two places or multiply by 100
11:23
that's 15% right and then I'm also going
11:26
to turn one over five into a percentage
11:28
right now it's one of those easiest
11:29
fraction so how do I turn one to
11:34
percentage I can use this over x 100 or
11:37
I could just times this by what 20 right
11:40
so this should be 20% if you do it right
11:42
so that be 20% right so email is 20%
11:46
text is 21% I is 15% so which one is the
11:50
preferred way of communication text
11:52
messages and it's still 21% it's still
11:55
two to this day right you guys like you
11:57
guys have lost the ability to
11:58
communicate excuse me because you're
12:00
afraid of talking right okay so most
12:02
people just like T most most most
12:07
teenagers boyfriend girlfriend through
12:10
text messaging can't talk to girlriend
12:13
you can't you see school you like and
12:16
thenex me you got bed you know that's
12:19
that's kind of like that's not even true
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