Multiplication — introduction

So far you've known how to add and subtract. In 2nd grade you'll meet a new math operation — multiplication. And you'll like it, because it's a shortcut.

When we need multiplication

Picture three baskets. In each basket there are four apples.

How many apples do you have altogether? You could count it like this:

4 + 4 + 4 = 12

But that's long. Multiplication writes it shorter:

3 × 4 = 12

We read it: "three times four equals twelve". The sign × means multiply.

When multiplication doesn't work

Watch out — multiplication is a shortcut only when all the groups are the same size.

• 3 baskets with 4 apples each — that's 3 × 4 ✓
• Baskets with 4, 5, and 3 apples — that's not multiplication, because the groups aren't equal. Add normally: 4 + 5 + 3.

Words you'll remember

• Multiplication — the operation.
• Factor × factor — the two numbers you multiply.
• Product — the result of multiplication.

In the example 3 × 4 = 12:

• 3 and 4 are the factors.
• 12 is the product.

What you'll learn in this topic

The next articles will show you:

• Multiplication as repeated addition — where it all comes from.
• Multiplication as an array — a neat rectangular picture.
• Tables 2, 5, 10 — the three easiest tables to start with.
• For parents — how to practise at home.

Summary

• Multiplication is fast addition of equal groups.
• We use the sign ×.
• The numbers we multiply are called factors, the result is the product.
• It only works when the groups are the same size.