# Fixed Number Subtraction Worksheets

Before we begin to present students with the concept of fact families and how addition and subtraction are related, we need to get them to be solid on basic subtraction skills. This is often a much more difficult operation for students to grasp because in effect it is counting in a reverse direction when they learned to count in a forward fashion. On this page we are sharing with you a technique that has been found to increase their ability to do this mentally. This is the ultimate goal with this operation. These worksheets have students work towards mastery of subtraction by having a set subtrahend for all the problems on that page.

### Aligned Standard: Related to 1.OA.A.1

- What Is A Fact Family?- It took 9 teachers 3 hours to agree on a full explanation for this one!
- Complete the Fact Families - Fill in the missing part or whole. Love the trees.
- Subtraction Facts Chart 1-6 - All the facts are here from zero to eleven.
- Subtraction Facts Chart 7-12 - Round two, but we start at seven.
- Subtraction Facts Chart with Missing Numbers for 1 and 2 - The rest of this set can be found below.

### Subtraction Facts Charts

Here are the remaining sets.

- Missing Numbers for 3 and 4 - These are fix values for the subtrahend portion of the problem.
- Missing Numbers for 5 and 6 - Get yourself into a rhythm with these types of problems.
- Missing Numbers for 7 and 8 - Once you get the hang of these it becomes automatic.
- Missing Numbers for 9 and 10 - The tens are pretty simple to work with, pretty much the same as one.

### Fixed Number Subtraction Sheets

We subtract by a set number. You will find some duplicates throughout the sheet for repeated practice

- Zero Subtraction - Solve for the following subtraction problems.
- Subtracting One - These problems are spread into three columns.
- Subtracting Two - You might want to count out these problems.
- Threes - This will help you form a mental math wave.
- Fours - See if taken away four does a body good.
- Fives - Fun fact: Five is the only prime number that is the sum of two consecutive primes.
- Six - This loosely referred to as "the first perfect number".
- Seven - That good ole lucky number.
- Eight - Turned on it side it means an never ending number.
- Nine - Fun fact: September is the ninth month of the year and also is composed of nine letters.
- Ten - The Roman numeral that represents this is the good ole "X".
- Eleven - Cool fact about eleven: World War I ended on the eleventh day of the eleventh month at the eleventh hour of the day.
- Twelve - The largest integer that is composed of one syllable.

### What is Fixed Number Subtraction?

When we are processing this operation, we have a starting value that we are removing a value from. We often refer to this as the act of taking away. A subtraction problem has three main actors, besides the minus sign and possibly an equal sign. The minuend is the value that we are starting with. The subtrahend is the amount we are removing that starting value. When we process this operation, the left-over value is called the difference. It follows in this skeleton: minuend - subtrahend = difference.

A technique that usually yields a higher level of comprehension, when teaching this, is using fixed values as either minuend or the subtrahend. Meaning that if you choose the fixed value of the minuend to be 6, every problem that the student is subjected to has 6 as the minuend and the subtrahend is either equal to that value or lesser. I would always start this off with the fixed number being the minuend. As students progress, you can flip flop this and use fixed subtrahends. Using this technique, you will find that students speed up their ability to process these much more accurately. Mental arithmetic also comes much faster to students, and you will start to see them no longer using their fingers to process these calculations. For students who need a more concrete approach, try using place blocks. You really want to build them up to using the fixed number of twelve (12). When you advance pass this value, it is time to introduce them to concept of place values and their ones and tens.

Students will often begin this process by counting backward. For example for the equation: 9 - 3, they will start at 9 and count backward 3 spaces (9, 8, 7, 6). While this is a good starting strategy, if you get them too dependent on this technique, they will have problems when we get to 3-digit values and higher. This again is where place value concepts come in handy.