Is 4 odd or even Easy

The question

Question: is 4 odd or even?

Even means it makes pairs, with none left over.

Odd means one is left over.

1 Make pairs

Here are 4 dots in pairs.

A pair is 2.

Ring each pair.

Every dot has a partner.

2 Odd or even

None left over.

So 4 is even.

3 Check

We count by 2s: 2, 4.

We land on 4.

Yes!

It works.

Let's look back.

First: make pairs.

Then: odd or even.

Last: check.

▶ Watch it solved

Is 20 odd or even Medium

The question

Question: is 20 odd or even?

Even means it makes pairs, with none left over.

Odd means one is left over.

1 Make pairs

Here are 20 dots in pairs.

A pair is 2.

Ring each pair.

Every dot has a partner.

2 Odd or even

None left over.

So 20 is even.

3 Check

We count by 2s: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20.

We land on 20.

Yes!

It works.

Let's look back.

First: make pairs.

Then: odd or even.

Last: check.

▶ Watch it solved

Is 23 odd or even Harder

The question

Question: is 23 odd or even?

Even means it makes pairs, with none left over.

Odd means one is left over.

1 Look at the ones

23 is 20 and 3.

Every ten makes 5 pairs.

So 20 is all pairs.

Only the 3 ones are left to check.

2 Put the ones in pairs

Here are 3 dots in pairs.

A pair is 2.

Ring each pair.

One dot has no partner.

3 Odd or even

One is left over.

So 23 is odd.

4 Check

We count by 2s from 20: 20, 22, 24.

We jump over 23.

23 is not on the list.

Yes!

It works.

Let's look back.

First: look at the ones.

Then: put the ones in pairs.

Then: odd or even.

Last: check.

▶ Watch it solved