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### Course: 7th grade foundations (Eureka Math/EngageNY) > Unit 4

Lesson 1: Topic A: Foundations# Finding a percent

Discover how to calculate percentages with this simple method. First, write the problem as a fraction, then simplify it. Next, convert the fraction to a percentage by making the denominator 100. Alternatively, divide the numbers to get a decimal and multiply by 100 to find the percentage. Master this skill for everyday use. Created by Sal Khan.

## Want to join the conversation?

- could a percent go over 100(64 votes)
- It can, yes. If you get extra credit on a test, the score could go over 100%, for example. If something is too big to fit into something, you could say it takes up 110% of the box, but that is a bit figurative.(119 votes)

- I'm confused on this problem. "Jordan takes 50% of the cherries from a bowl. Then Mei takes 50% of the remaining cherries. Finally, Greg takes 50% of the remaining cherries. There are 3 cherries left. How many cherries were in the bowl before Jordan arrived?" Can I get help on this please?(13 votes)
- Each time someone takes 50% (or half) of the remaining cherries, the other half of them are left.

1/2 of the original number of cherries are left, just after Jordan takes the cherries.

(1/2)(1/2)=1/4 of the original number of cherries are left, just after Mei takes the cherries.

(1/2)(1/4)=1/8 of the original number of cherries are left, just after Greg takes the cherries.

Since there are now 3 cherries left, there were originally 3*8=24 cherries. The answer is 24.(52 votes)

- how do you find 111 is what percent of 300(12 votes)
- Divide: 111/300

And, multiply by 100.

In other words: 111/300 * 100/1 = the percent that you want

See if you can finish the math.(37 votes)

- math should solve their own problem, this is hard(24 votes)
- what if you keep adding 0s but you can't get a remainder or answer?(8 votes)
- The only way this would happen is if it is a infinite repeating number like pi or 3/7. Both of these numbers will never end no matter how much decimal places you move with the 0. These numbers can be confusing. To limit this, round to the ones, tens, hundreds, or thousandths to prevent repeating digits.

Hope this helps!(23 votes)

- This video doesn't help with the questions at ALL! I struggled with the questions so much! It seriously didn't help. Some of the questions didn't use the same methods which just made it harder. Didn't help at all...(15 votes)
- that what im saying(5 votes)

- do we have to finish all the videos(8 votes)
- I'm so glad you asked! I am a helper here at Khan Academy. I would like to let you know that watching the videos would help you learn more knowledge, and they help you gain energy points. You are not required to watch the videos but they have 2 advantages as said above.(17 votes)

- can you try to explain more(13 votes)
- like the teacher said in the video you can use one forth of 16 as an example and use that. After you multiply it by twenty-five and that gives you 25/100 because four is a 4th of sixteen aka a 25th of one hundred. Another problem is 5/10 what is the percentage of the five? Well multiplying the by 5 and 10 by 10 you get 50/100 aka one half of one hundred.(1 vote)

- I'm having trouble understanding word problems. How did they get the fraction 4/16 from the question?(8 votes)
- He had the numbers 4 and 16. So he just divided them (i.e. 4/16).(4 votes)

- could a percentage go over a thousand?(4 votes)
- Yes, it could. A percentage could possibly be any number, even in the millions.(3 votes)

## Video transcript

Let's give ourselves
a little bit of practice with percentages. So let's ask ourselves, what
percent of-- I don't know, let's say what
percent of 16 is 4? And I encourage you
to pause this video and to try it out yourself. So when you're saying
what percent of 16 is 4, percent is another way of
saying, what fraction of 16 is 4? And we just need to write
it as a percent, as per 100. So if you said what fraction
of 16 is 4, you would say, well, look, this is
the same thing as 4/16, which is the same thing as 1/4. But this is saying what
fraction 4 is of 16. You'd say, well, 4 is 1/4 of 16. But that still doesn't
answer our question. What percent? So in order to write
this as a percent, we literally have to write
it as something over 100. Percent literally
means "per cent." The word "cent" you know
from cents and century. It relates to the number 100. So it's per 100. So you could say,
well, this is going to be equal to question mark
over 100, the part of 100. And there's a bunch of ways
that you could think about this. You could say, well, look,
if in the denominator to go from 4 to 100, I
have to multiply by 25. In the numerator
to go from-- I need to also multiply by 25 in order
to have an equivalent fraction. So I'm also going
to multiply by 25. So 1/4 is the same
thing as 25/100. And another way of saying 25/100
is this is 25 per 100, or 25%. So this is equal to 25%. Now, there's a
couple of other ways you could have thought about it. You could have said
well, 4/16, this is literally 4 divided by 16. Well, let me just
do the division and convert to a
decimal, which is very easy to convert
to a percentage. So let's try to actually do
this division right over here. So we're going to
literally divide 4 by 16. Now, 16 goes into 4 zero times. 0 times 16 is 0. You subtract, and you get a 4. And we're not satisfied
just having this remainder. We want to keep adding zeroes to
get a decimal answer right over here. So let's put a decimal
right over here. We're going into
the tenths place. And let's throw some
zeroes right over here. The decimal makes sure
we keep track of the fact that we are now in the
tenths, and in the hundredths, and in the thousandths place
if we have to go that far. But let's bring another 0 down. 16 goes into 40 two times. 2 times 16 is 32. If you subtract, you get 8. And you could bring
down another 0. And we have 16 goes into 80. Let's see, 16 goes
into 80 five times. 5 times 16 is 80. You subtract, you have no
remainder, and you're done. 4/16 is the same thing as 0.25. Now, 0.25 is the same thing
as twenty-five hundredths. Or, this is the same
thing as 25/100, which is the same thing as 25%.