Add and Subtract 10s

π€ Do you remember the **multiples of 10?**

10, 20, 30, 40, 50, 60, 70, 80, 90

You've worked with these numbers before. Let's review that today! π€

π€Do you remember the **place values **of multiples of 10?

π They all have **only Tens place values!** Their Ones place values are **0.**

Let's look at an example.

26 + 10 = ?

The second number is a **multiple of 10**.

Can you tell **which digit will change** during addition? π€

Correct! π Only the **Tens place **will change!

Great job! π The answer is **36.**

26 +10 =36

π Let's try another problem.

**30 + 27 = ?**

One of the numbers is a **multiple of 10.**

So, again, only the **Tens place **will change! π€Β

Nice work! π€ The answer is **57.**

30 +27 =57

π Let's now try a **subtraction **problem.

**74 - 30 = ?**

The **subtrahend **(smaller number) is a **multiple of 10**.

So, once again, only the **Tens place **will change! πΒ

Great work! The answer is **44.**

74 -30 =44

Let's try one more.

**80 - 20 = ?**

Go ahead! You got this!

Awesome! π The answer is **60.**

80 -20 =60

Sometimes, we may have questions about multiples of ten. π€

For example π

3Tens+ 4Tens=?

or

What isten less than45?

Do you know how to solve them?

ππThe trick is tolook for clues!ππ

Let's take the first example.

**3 Tens + 4 Tens = ****?**

What **clues **do you see?

π The word **'Tens' **tells us that the numbers have only Tens place values.

π The **'+' symbol** tells us that this is an addition problem.

π€ Do you think you can solve the question now?

Go ahead! π€Β

30 +40 =70

or

3Tens +4Tens =7Tens

Great job! π

Let's try the other problem now.

What is *ten less than ***45**?

**Clues:**

π The word **'ten' **tells us that we have to add/subtract a multiple of 10.

π The words **'less than' **tell us that this is a subtraction problem.

Go on! Solve the question! π€

45 -10 =35

or

Tenless than45is35.

Amazing! π

Try this one now.

What is *ten more than ***89?**

**Clues:**

π The word **'ten'.**

π The words **'more than'.**

So, what's the answer? π€

89 +10 =99

or

Tenmore than89is99.

Great work! You got it now! π

Now, you can practice what you've learned! π€Β

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