Decimals by Decimals Division

Introduction

In this topic we will discuss the method to dividing a decimal by a decimal. This is a very easy topic as long as you know your decimal place values. So let's get going!

Decimal Division

Let's say that we have the problem 2.55/1.5

The first step is to make the divisor into a whole number. In order to do that, we need to move the decimal point in 1.5 from left to right as many times as we can so that 1.5 becomes a whole number:

1.5 moved 1 place from left to right becomes 15.

We have to do the same thing to the dividend: move it one place from left to right:

2.55 becomes 25.5

Now, we'll just do some simple division:

25.5/15

     

     _1.7____

15[25.5

-    15

_________

      105

-     105

_________

         0

That means that the quotient of 2.55/1.5 equals 1.7!

Sheet 1 Decimal by Decimal Division

Inserting Zeros when Adding/Subtracting Decimals

Introduction

When you are adding or subtracting decimals you will often come across problems with decimals that may be missing a digit in various place values. Well, in this lesson, we will learn how we can insert zeros in the empty spaces to make the addition or subtraction easier for us!

Inserting Zeros for Addition

Let's say that we have a problem such as 24.5+3.2. 

Remember that when you are adding or subtracting decimals, the decimal point needs to line up one on top of the other:

  24.5

  +3.2

Now, as you can see, there is no digit in the tens place for the decimal number 3.2.

This is when you can insert a zero in the place where there are no digits.

Why add a zero?

Because zero holds no value so it won't change our problem!

  24.5

+03.2

  27.7

That means that the sum of 24.5+3.2 equals 27.7!

Inserting Zeros for Subtraction

Let's say that we have the problem 18.79-12.3.

Now as you can see, there is no digit for the hundredths place in the decimal number 12.3. 

This is when we insert a zero in the place where there are no digits.

 18.79

-12.30

---------

 06.49

That means that the difference of 18.79-12.3 equals 6.49!

Sheet 1 Inserting Zeroes when Adding or Subtracting Decimals