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Strategies for multiplying multi-digit decimals by whole numbers

Learn how to multiply decimals and whole numbers. The video presents two strategies: converting decimals to tenths and multiplying, then converting back, and using estimation to determine where the decimal should go in the answer. Both methods reinforce understanding of place value. Created by Sal Khan.

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• i watched every video and i still don't get it i still need help
• you take the decimal away and multiply.then,you put the decimal point the number of places to the left of the number by the number of places to the left of the numbers you're multiplying by. make sense?
• What do you do if the decimal is a number like 7475.92? That would definitely be hard to multiply, right? I really hate doing really long multi-digit multiplication problems. 😥😥😥 It takes A LOT of time to solve, and I want to use the most less time.
I know that was really long, but somehow, I got it out of me.
• You just multiply it like you usually would. The only difference is that your adding a decimal in with your equation. Though, its important that you don't forget to add the decimal when your multiplying because that can change your answer dramatically, and sadly can mess you up on your answers. Be sure to also check your work step-by-step once your finished to make sure you didnt forget any steps or make errors. I know this is a lot of steps, but they are important so that you get these things correct. Its also not a good option to forget any of these things. Im in 7th grade and I still to this day use long digit multiplication for more subjects than just math, even science.
• there is an easier way to figure out how many decimal places will be in your answer. let's say you have one decimal place in the question, then the answer will have 1 decimal place b/c there's one decimal in the question.
ex.
45.3 times 6 = 271.8
this is more helpful when you have two decimals tho
• that and you have to count total decimals in both numbers, so 45.3^.6=27.18.
• why do you take the hard way just move the decimal
• How do I know where I put the decimal? What if I think that I had only a place for a tenth, ones, tenths, and hundreths? Get what I mean?
• You can find out where to put the decimal with this simple example!:
0.02 X 0.3
0.02-------> 2
0.3--------> 3
2*3 =6
OG Problem: 0.02 x 0.3
Altogether there is 3 spaces to the right of the decimal point so you would start behind the 6, like so: 6. After this you would move it 3 spaces: 0.0.0.6.
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• decamals are kinda hard for me i still need help....
• how can i divide by decimels ?