Multi-Digit Multiplication — Intro

How the lesson starts: Multi-Digit Multiplication — Intro

Kip feeds the penguins
Hi there! Kip the zoo keeper feeds the penguins. Each bucket holds 23 fish. Kip carries 4 buckets. How many fish in all? That's 23 × 4. Let's split it up!
Two boxes to multiply
23 is 20 + 3. Draw a box model. The top shows 20 and 3. The side shows 4. First box: 20 × 4 = 80. Second box: 3 × 4 = 12. Add the parts: 80 + 12 = 92 fish!
A bigger bucket
The seals get 87 fish, 5 times. So 87 × 5. Split 87 into 80 + 7. 80 × 5: think 8 × 5 = 40, so 400. 7 × 5 = 35. Total: 400 + 35 = 435. Watch out: the 8 means 80, so it's 400, not 40!