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### Course: 4th grade>Unit 9

Lesson 3: Multiplying whole numbers and mixed numbers

# Multiplying mixed numbers by whole numbers

Sal uses repeated addition to help multiply a whole number by a mixed number.

## Want to join the conversation?

• can anyone explain how 2 1/4 became
8/4 + 1/4??
• Kinda stupid of me replying but I don't understand either but I think 2 1/4 becomes 8/4 because 2x4=8 or maybe 2x1=2 I don't really know so don't judge me :(
• First of all, 9 X 4 IS 36 NOT 27, 27 IS 9 X 3
• yes that is correct even tho i dont really know much about multipulcation
• where did you get the number (8/4 + 1/4) from
• This is what he did:
2 1/4 (mixed number)
2 + 1/4 (2 wholes, 1/4 part)
2*4/4 + 1/4 (4/4 = 1 so there's no change to the expression)
8/4 + 1/4
9/4
Hope it helps anyone
• 2 1/4x3
2x1=2
2x3=6, I'm I doing it wrong?
I don't understand.
• Exe, to make it easier, you should convert 2 1/4 into an improper fraction

The improper version of 2 1/4 is 9/4.

BUT, 9/4 x 3, can be made even EASIER.

All whole numbers, positive or negative, have a fraction version.

All of them are 'something'/1.

3 can be interpreted as 3/1.

So, 9/4 x 3/1 is 27/4.

27/4's mixed number form is 6 3/4.

Hope this helps, Exe.
• _ 6 + 3/4 is just 6 3/4? I thought we had to find the lowest common denom. to add fractions, not just tack 6 onto 3/4. what am I missing?
• i always watch this video but then i get a 0 on the excersises lol sal plz explain more
• I can't submit! 😶