We’re asked to identify the

percent, amount, and base in this problem. And they ask us, 150 is

25% of what number? They don’t ask us to solve it,

but it’s too tempting. So what I want to do is first

answer this question that they’re not even asking

us to solve. But first, I want to answer

this question. And then we can think about what

the percent, the amount, and the base is, because

those are just words. Those are just definitions. The important thing is

to be able to solve a problem like this. So they’re saying 150 is

25% of what number? Or another way to view this,

150 is 25% of some number. So let’s let x, x is equal

to the number that 150 is 25% of, right? That’s what we need

to figure out. 150 is 25% of what number? That number right here

we’re seeing is x. So that tells us that if we

start with x, and if we were to take 25% of x, you could

imagine, that’s the same thing as multiplying it by 25%, which

is the same thing as multiplying it, if you

view it as a decimal, times 0.25 times x. These two statements

are identical. So if you start with that

number, you take 25% of it, or you multiply it by 0.25, that

is going to be equal to 150. 150 is 25% of this number. And then you can solve for x. So let’s just start with

this one over here. Let me just write it separately,

so you understand what I’m doing. 0.25 times some number

is equal to 150. Now there’s two ways

we can do this. We can divide both sides of this

equation by 0.25, or if you recognize that four quarters

make a dollar, you could say, let’s multiply both

sides of this equation by 4. You could do either one. I’ll do the first, because

that’s how we normally do algebra problems like this. So let’s just multiply

both by 0.25. That will just be an x. And then the right-hand side

will be 150 divided by 0.25. And the reason why I wanted to

is really it’s just good practice dividing

by a decimal. So let’s do that. So we want to figure out what

150 divided by 0.25 is. And we’ve done this before. When you divide by a decimal,

what you can do is you can make the number that you’re

dividing into the other number, you can turn this into

a whole number by essentially shifting the decimal

two to the right. But if you do that for the

number in the denominator, you also have to do that

to the numerator. So right now you can view

this as 150.00. If you multiply 0.25 times

100, you’re shifting the decimal two to the right. Then you’d also have to do

that with 150, so then it becomes 15,000. Shift it two to the right. So our decimal place

becomes like this. So 150 divided by 0.25

is the same thing as 15,000 divided by 25. And let’s just work it

out really fast. So 25 doesn’t go into 1, doesn’t

go into 15, it goes into 150, what is that? Six times, right? If it goes into 100 four

times, then it goes into 150 six times. 6 times 0.25 is– or actually,

this is now a 25. We’ve shifted the decimal. This decimal is sitting

right over there. So 6 times 25 is 150. You subtract. You get no remainder. Bring down this 0 right here. 25 goes into 0 zero times. 0 times 25 is 0. Subtract. No remainder. Bring down this last 0. 25 goes into 0 zero times. 0 times 25 is 0. Subtract. No remainder. So 150 divided by 0.25

is equal to 600. And you might have been able

to do that in your head, because when we were at this

point in our equation, 0.25x is equal to 150, you could

have just multiplied both sides of this equation

times 4. 4 times 0.25 is the same

thing as 4 times 1/4, which is a whole. And 4 times 150 is 600. So you would have gotten

it either way. And this makes total sense. If 150 is 25% of some number,

that means 150 should be 1/4 of that number. It should be a lot smaller than

that number, and it is. 150 is 1/4 of 600. Now let’s answer their

actual question. Identify the percent. Well, that looks like 25%,

that’s the percent. The amount and the base

in this problem. And based on how they’re wording

it, I assume amount means when you take the 25% of

the base, so they’re saying that the amount– as my best

sense of it– is that the amount is equal to the percent

times the base. Let me do the base in green. So the base is the number you’re

taking the percent of. The amount is the quantity

that that percentage represents. So here we already saw

the percent is 25%. That’s the percent. The number that we’re taking

25% of, or the base, is x. The value of it is 600. We figured it out. And the amount is 150. This right here is the amount. The amount is 150. 150 is 25% of the

base, of 600. The important thing is how

you solve this problem. The words themselves, you know,

those are all really just definitions.

Good one – doing it in slow motion and color coded.

thanks a lot 🙂

good video

Is/Of = %/100

cool, what program r u usin?

People are always asking me where i go to school. I tell em khanacademy

just do this

150 * 100/25

۞

My dad's whole family is full of teachers….after I learn from this, I'm gonna pass this gift called KhanAcademy on to them.

dota players are so lucky, these percent problems are a bit easy for them

Anyone notice at 3:12 he draws a cat face

Anyone know what software/inputs he is using to create this video?

just multiply the % by the number

what program is that ?? 🙂

what confused……………….

8(

In Khan we trust!!!!! <3

This is still very hard .

Nadia took two practice exams to prepare for her college entrance exam. On the first practice exam, she scored one thousand one hundred. After studying, her score increased by thirty percent. What was her score on the second practice exam?

one thousand one hundred thirty

one thousand four hundred

one thousand four hundred thirty

one thousand five hundred seventy-one

This was on my flvs class 😀 awesome

u r a life saver!!

I am going to use your work to study for the GRE, but I don't know which book you're using? Please let me know, thanks!

Dude! You so rock! Thanks for your help!

it all makes sense now

THAnks man you helped i wondering if i should subscribe

hi

subscribe to Destroyer_Of_All

hi i hope u can help me. I am looking for a formula to fin the following:

I need to know 3 things. subtotal, 7% of subtotal, total (sum of subtotal and 7%)

I have the total which is 4100 and i know the percent used to calculate that is 7%…how can I find out which the SUBTOTAL number should be?

THANK YOU

Daurde Sandstorm

At 3:03 when he was writing 150 as 150.00 and then he was carrying the decimal, the two zeroes at the end of it wight he carried decimal line under it made it look like a :3 face. lol

khan acedemy

I have been watching your videos for YEARS and I cannot thank you enough for all the help you've given me!!!!!!!

these vidieos are geting me through school. i went in to school unconfodent but now iam cofodent and ready for a test

Khan Academy all the way

You go way to fast in all of your videos, still love you though.

thank you sooo much helps me alot

I just did 150×4 and I got 600 ._.

u know war u r awesome

THX THX THX

You could have just done 4*150

So what Is 150 25% of? Oh lemme see. Since 4 quarters make a dollar. (25×4=100) so that means 150×4=600 since 150 is only a quarter of the number. Yall make it overly complicated for no reason.

thx very helpful u r awsome

😉

It is easy

Can u do a video with percents with proportion

iiiy papi

Thanks for doing the process instead of using a calculator

In the First 1:53 minutes I was saying the mans a Genius.

it doent understand wath a shit

=(((((

You do all of you act like jerks who try teach you important academic skills needed in your life. Micheala im talking to you

cool

Thx really helpful. But still not sure

you now well fock you

there is no sound

To solve percentage I think it's much easier to use what we call " Regra de três" ( rule of tree, literally). In this problem it was obvious that we could multiply for 4, but in other cases this way is better. (IN MY OPINION).

150= 25 | 25x = 150.100

X = 100| X = 15000/25=600

(reading:

If 150 is 25% of X, so X is 100%.

150 times 100 is equal 15000;

25 times X is equal 25X ;

— you can take out the last two zeros if you want to make it easier, and at the end you add them back.—

So 150 by 25 is 6 (plus those two zeros you took off before) it is 600.

I hope you got it, I'm not a native English speaker, I'm just trying to help.

you could also do 150+150+150+150 =600

Or you can just do 150×4

So this is the slower way

150 is 25% of 600

I really don't understand to solve by using the formula triangle can you make a video about the formula triangle

look at the bottom right corner of 3:26 you see my face

you help me

i still do not understand

This is confusing.

thanks

Green screen?

tnx you help me

@1:32 — what is the "it" ??

Thank u

I have to watch this for test corrections

You cn alw

You can always just do 150×25-.

WOW this really helped out with my test

this is useful

By the 1st minute I was able to understand very clearly. Thank you.

THANK YOU

We can solve it much easier by multiplying 150 by 25 then divide it by 100 that will answer 600

🙏 thank you I was so confused about this until I seen this video sorry for my bad grammar

I do not get it

150 times 4 bam answer

Admit it. You're here because you have a test😅

Who else is watching this for a last-minute test?

wrong video 4 me

lol i found de wrong video

wow, this guy is a GENIOUS… MY MIND IS BLOWN

60-0 equals 60 not 0

Who owns khan acadamy

:[] ……………………………

this is a grate video

Still makes no sense

You could have timed it by 4

is not 37.5?

This video is for nine years of people cramming for a test.

you could have saved time by just multiplying 150 into 4

SAVED ME FROM THIS HOMEWORK 🤢💘

Ohhhhhhhhhhh after I watched I finally understand clearly.

We could have done this method

25

_ × 100

150