Course summary field: Multiply multi-digit numbers confidently, plus a shortcut for multiplying by 10, 100, and 1,000.
Multiplication is really just fast repeated addition. 6 × 4 means “6 groups of 4,” which is the same as 4 + 4 + 4 + 4 + 4 + 4. Once numbers get bigger, though, we need a system, and that’s where carrying comes back in, just like in addition.
Example 1:
6 × 8 = 48 → write 8, carry the 4
6 × 2 = 12, plus the carried 4 = 16 → write 6, carry the 1
6 × 3 = 18, plus the carried 1 = 19 → write 19
Answer: 1,968
Multiplying two 2-digit numbers takes an extra step: you multiply by each digit separately, then add the results
First, multiply 47 × 3 = 141
Then, multiply 47 × 20 = 940 (multiply by 2, then add a zero, since it’s really “20”)
Add them together: 141 + 940 = 1,081
✨The 10 / 100 / 1,000 shortcut: When multiplying by 10, 100, or 1,000, you don’t need to do any carrying at all, just tack on that many zeros.
47 × 10 = 470 (add 1 zero)
47 × 100 = 4,700 (add 2 zeros)
47 × 1,000 = 47,000 (add 3 zeros)
⚡Quick tip: Think of it like a video game high score, every extra zero you multiply by “levels up” the number by one more zero at the end.
Level up! you just learned a whole new lesson! for more practice solve lesson 9 from our booklet.