Currently a HS freshman with ADHD relearning math from the absolute basics, just cleared this unit. I'm proud of myself :)

I am in a similar situation. This is a valuable resource, indeed!

omg this is hard for me 2 learn i really need help

try your best! think positive you guys can do it!💖

It stands for "Frequently Asked Questions"

Did any of y'all know that there is games on Khan academy

u go to courses and find computer programming (at the bottom ) and click on it and scroll to the bottom

Ok, so what you're gonna want to start of with is setting it up for ex. 29 x 10 ------ then multiply, 29 x 10 ------ 2900

what is 10 x infinity?

You can't multiply infinity, so it'd _stay_ infinity. Just like how if you multiply 10 x 0, it'd stay 0.

Main content

Course: 5th grade > Unit 5

Lesson 4: Multi-digit division

Multi-digit multiplication and division: FAQ

Google Classroom

Frequently asked questions about multi-digit multiplication and division.

Why do we need to learn multi-digit multiplication and division?

There are many situations in the real world where we need to multiply or divide numbers that are larger than just one digit. For example, if we want to calculate the cost of

17

items that each cost

12

, we'll need to multiply

17 \times 12

How can we estimate multi-digit multiplication and division problems?

One way to estimate is to round each number to the nearest ten, hundred, or thousand (depending on the size of the numbers) and then multiply the rounded numbers together. For example, to estimate

238 \times 24

, we could round each number to the nearest ten:

240 \times 20 = 4,800

For division, we can estimate the dividend and divisor to the nearest ten, hundred, or thousand (depending on the size of the numbers) and then divide the rounded numbers. For example, to estimate

314 \div 27

, we could round each number to the nearest ten:

310 \div 30 = 10

Try it yourself with these exercises:

Why do we need to learn how to factor out multiples of ten when multiplying and dividing?

Working with multiples of ten is often easier because of the way our base-ten number system is structured. So, by factoring out tens, we may be able to break down a difficult multiplication or division problem into a simpler one.

Try it yourself with these exercises:

What is the standard algorithm for multiplication and how do we use it?

The standard algorithm for multiplication involves breaking one of the numbers down into its place values, multiplying each place value by the other number, and then adding the results together.

For example, we can use the standard algorithm to multiply

83 \times 9

First, we multiply

9 \times 3

\begin{aligned} \overset{2}{8} \overset{}{3} \\ \underset{―}{\times 9} \\ 7 & 9 \times 3 = 27 \end{aligned}

Next, we multiply

(9 \times 80) + 20

\begin{aligned} \overset{2}{8} \overset{}{3} \\ \underset{―}{\times 9} \\ 747 & (9 \times 80) + 20 = 740 \end{aligned}

Try it yourself with these exercises:

What are remainders and how do they relate to division?

The remainder is the amount left over when you divide one number by another and the division doesn't come out evenly. For example, if we divide

10

2

, we get a whole number result of

5

, with no "leftovers." But if we divide

10

3

, you get a result of

3

with a remainder of

1

Try it yourself with these exercises:

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calhvnson
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omg this is hard for me 2 learn i really need help
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so we are learning about a standard algorithm for multiplication and also who in the world is destiny.
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hehe rip club penguin
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what is 10 x infinity?
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how do you solve long division in your brain (not mentally)?
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This is so hard...
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- Gavin
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  Ok, so what you're gonna want to start of with is setting it up for ex.
  29
  x 10
  ------
  then multiply,
  29
  x 10
  ------
  2900
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How do you estimate multpication I still don't understand
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