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### Course: Numbers & Operations - The Real & Complex Number Systems 201-210>Unit 3

Lesson 4: Multiply with partial products

# Multiplying 3-digit by 1-digit

Learn to multiply a 3-digit number by a 1-digit number without regrouping.  In this video, we will multiply 4x201. Created by Sal Khan.

## Want to join the conversation?

• 201x4... easy! 1.Just multiply 200x4 2. Then multiply 4x1 3. Last add the products 800+4=804

I hope this helps
• Hi
is it always just me or are the videos easy but the test are really hard.

see you next time!
• wach the vido 5 times
(1 vote)
• Has anyone ever heard of lattice multipliation?
• I don't know what is "lattice multiplication".
• Hi!

My question is pretty random, but can you ÷ using the same standered way we're using?
I know it works for addition, subtration and multiplacation!

Thanks!
• yes you can :D
• He never finished the problem. His problem was 4x2012 which is 8048, but he did 4x201!
• is a, for example, a 50 digit number ( YES,A 50 DIGIT NUMBER!), times another 50 digit number,possible? Wouldnt end up as a 100 digit number?
• great job!but i still cant figure 1*1?
• Any number multiplied by 1 is the number itself. So 1*1 = 1, 1*2 = 2, 1*3 = 3, and so on. If you are a visual learner then think of it like this: if you have one group of strawberries and that group has one strawberry in it then how many strawberries are there? The answer is 1.