Math Core

You know how to take things away. Now you can write it down with numbers, using a new sign: the minus sign.

The minus sign

The sign $-$ means take away. It is called minus.

The sign $=$ means is the same as. It is called equals.

Reading a subtraction sentence

$4 - 1 = 3$

Say it like this: "Four minus one equals three." Start with 4. Take away 1. You have 3 left.

The first number is how many you start with. The number after the minus sign is how many you take away. The number after the equals sign is how many are left.

Use your fingers

Hold up the first number of fingers. Put down the number you take away. Count the fingers that are still up.

Worked example: Stars

Find $3 - 1$ .

⭐ ⭐ ❌

Start with 3 stars. Take away 1. Two stars are left.

$3 - 1 = 2$

Worked example: Fingers

Find $5 - 2$ .

Hold up 5 fingers. Put down 2. Count the fingers still up: one, two, three.

$5 - 2 = 3$

Worked example: Take away nothing

Find $4 - 0$ .

🐞 🐞 🐞 🐞

Start with 4 ladybugs. Take away 0, so none go away. You still have 4.

$4 - 0 = 4$

Tip

Taking away 0 leaves the same number. Taking away all of them leaves 0. For example, $3 - 3 = 0$ .

Common mistake

Always start with the first number. $5 - 2$ means start with 5 and take away 2. It does not mean start with 2.

Practice

Practice 1

Find $2 - 1$ .

🍌 ❌

Type a number.

Practice 2

Find $4 - 2$ .

🌸 🌸 ❌ ❌

Type a number.

Practice 3

Find $5 - 1$ .

Type a number.

Practice 4

Find $3 - 3$ .

Type a number.

Practice 5

Find $5 - 3$ .

Type a number.

Practice 6

Find $4 - 3$ .

Type a number.

Practice 7

Which picture shows $5 - 4$ ?