There are no videos explaining the use of brackets? It can be quite confusing to anyone learning for the first time when they try to solve any problem that includes braces and parenthesis.

brackets and perentheses are the same thing you just want to do the parentheses before the brackets like the teacher taught you parentheses first.

addition is an opperation so why did Sal say that he solved the problem without using operations even though he used addition?

So, he didn't really use the operation. He just wrote down what they were asking for. If he had actually performed the operation, he would have come up with 27, which is a number, not a numerical expression. Hope this helps.

my mom makes me do a unit a day cause she thinks im good at math

Thats good to know keep up the good work

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5th grade

Course: 5th grade > Unit 13

Lesson 1: Writing expressions

Constructing numerical expressions

Name: Constructing numerical expressions
Uploaded: 2013-08-21T16:39:51Z
Description: Sometimes, we don't need to solve an equation right away. Instead, we can use the information in a given word problem to construct a numerical expression that represents the information.

Google Classroom

Sometimes, we don't need to solve an equation right away. Instead, we can use the information in a given word problem to construct a numerical expression that represents the information. Created by Sal Khan.

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Jaime Garcia
Posted 10 years ago. Direct link to Jaime Garcia's post “There are no videos expla...”
There are no videos explaining the use of brackets? It can be quite confusing to anyone learning for the first time when they try to solve any problem that includes braces and parenthesis.
Button navigates to signup pageComment on Jaime Garcia's post “There are no videos expla...”
(45 votes)
Answer
- luna
  Posted 4 years ago. Direct link to luna's post “brackets and perentheses ...”
  brackets and perentheses are the same thing you just want to do the parentheses before the brackets like the teacher taught you parentheses first.
  Comment on luna's post “brackets and perentheses ...”
  (33 votes)
Humming Birb
Posted 3 years ago. Direct link to Humming Birb's post “I just lost my marbles tr...”
I just lost my marbles trying to understand this. Pun intended. :)))) It's easy tho
Button navigates to signup pageComment on Humming Birb's post “I just lost my marbles tr...”
(27 votes)
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Jaz
Posted 7 months ago. Direct link to Jaz's post “ngl who else be looking i...”
ngl who else be looking in the comments when their bored??
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(23 votes)
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- isacra2031
  Posted 20 days ago. Direct link to isacra2031's post “i do”
  i do
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  (1 vote)
Kam Wong
Posted 7 years ago. Direct link to Kam Wong's post “addition is an opperation...”
addition is an opperation so why did Sal say that he solved the problem without using operations even though he used addition?
Button navigates to signup pageComment on Kam Wong's post “addition is an opperation...”
(13 votes)
Answer
- hannahmorrell
  Posted 7 years ago. Direct link to hannahmorrell's post “So, he didn't really use ...”
  So, he didn't really use the operation. He just wrote down what they were asking for. If he had actually performed the operation, he would have come up with 27, which is a number, not a numerical expression.
  Hope this helps.
  Button navigates to signup page
  (6 votes)
david.mercado4272
Posted 2 years ago. Direct link to david.mercado4272's post “im the newest comment eve...”
im the newest comment ever since 7 yrs ago
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(11 votes)
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- strickland.adam
  Posted 8 months ago. Direct link to strickland.adam's post “Alan found 4 marbles to a...”
  Alan found 4 marbles to add to his 5 marbles currently in his pocket. He then had a competition with his friends and tripled his marbles. Write a numerical expression to model the situation without performing any operations. So let's think about what's going on. So he already had 5 marbles in his pocket. And then he found 4 more marbles to add to that. So we can add the 4 marbles to the 5 marbles. So 4 marbles plus the 5 marbles. So that's what happens after the first sentence. He found 4 marbles to add to his 5 marbles currently in his pocket. He then had a competition with his friends and tripled his marbles. So this is how many marbles he had before tripling. And now he's tripling his marbles. So we want to multiply 3 times the total number of marbles he has now-- times 4 plus 5. So this right over here is the numerical expression that models the situation without performing any operations. We, of course, could then actually calculate this. He has 9 marbles before tripling. And then you multiply it by 3 and he has 27. But this is what they're asking for. They want us to write this expression.
  Comment on strickland.adam's post “Alan found 4 marbles to a...”
  (1 vote)
hema.govindh
Posted 5 months ago. Direct link to hema.govindh's post “my mom makes me do a unit...”
my mom makes me do a unit a day cause she thinks im good at math
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(10 votes)
Answer
- chloelakole
  Posted 2 months ago. Direct link to chloelakole's post “Thats good to know keep u...”
  Thats good to know keep up the good work
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  (2 votes)
amay
Posted a year ago. Direct link to amay's post “math is a good subject to...”
math is a good subject to learn kade.dean30
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(10 votes)
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- isacra2031
  Posted 20 days ago. Direct link to isacra2031's post “no it is not.”
  no it is not.
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  (0 votes)
Çlåüdé
Posted a year ago. Direct link to Çlåüdé's post “Hello, this is helpful th...”
Hello, this is helpful thanks.
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(11 votes)
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- bryanwyattt
  Posted 9 months ago. Direct link to bryanwyattt's post “it 21!1”
  it 21!1
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  (0 votes)
Sabhya
Posted a year ago. Direct link to Sabhya's post “His is missing its 'h' it...”
His is missing its 'h' it looks is
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(8 votes)
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lilr3v3ng
Posted 4 months ago. Direct link to lilr3v3ng's post “who understands this”
who understands this
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(4 votes)
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- isacra2031
  Posted 19 days ago. Direct link to isacra2031's post “i do”
  i do
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  (0 votes)

Video transcript

Alan found 4 marbles to add to his 5 marbles currently in his pocket. He then had a competition with his friends and tripled his marbles. Write a numerical expression to model the situation without performing any operations. So let's think about what's going on. So he already had 5 marbles in his pocket. And then he found 4 more marbles to add to that. So we can add the 4 marbles to the 5 marbles. So 4 marbles plus the 5 marbles. So that's what happens after the first sentence. He found 4 marbles to add to his 5 marbles currently in his pocket. He then had a competition with his friends and tripled his marbles. So this is how many marbles he had before tripling. And now he's tripling his marbles. So we want to multiply 3 times the total number of marbles he has now-- times 4 plus 5. So this right over here is the numerical expression that models the situation without performing any operations. We, of course, could then actually calculate this. He has 9 marbles before tripling. And then you multiply it by 3 and he has 27. But this is what they're asking for. They want us to write this expression.