Subtraction

Subtraction is "the process or skill of taking one number or amount away from another" and/or "the process of taking a quantity away from another under specific rules to obtain the difference."

— Oxford Languages & Dictionary

Quick Overview of Subtraction:

There are five parts of subtraction: the minuend, the subtraction symbol, the subtrahend, the equal sign, and the difference

Example problem/equation: $64 - 23 = 41$

Terminology:

• Minuend - the number that is the starting amount in a subtraction equation. This number is always on the far left-hand side (LHS) of the equation and will become smaller when you find the answer. In the problem above, the minuend would be 64

• Subtraction Symbol ( - ) - this is how you know what operation the problem is. If the symbols look like [-] then it is a subtraction problem. In the problem above, the symbol, -, is shown so it is a subtraction problem

• Subtrahend - the number that is making the starting amount (minuend) smaller. This number is also always on the left-hand side (LHS) of the equation. In the problem above, the subtrahend would be 23

• Equal Sign - the symbol (=) in the middle of the equation. This symbol sets the left-hand side (LHS) EQUAL to the right-hand side (RHS)

• Difference - this is the final number in a subtraction equation and is the result of subtracting the minuend and subtrahend. This number will always be on the far right-hand side (RHS) of the subtraction equation. In the problem above, the difference is 41

Rules of Subtraction:

• Rule 1 - when subtracting two numbers. Make sure to deduct the right side of the subtraction side, from the left side. For example, $5 - 2$ is saying, take away 2, from 5. Not Take away 5 from 2.

• Rule 2 - when you're doing word problems and it uses the word "from" then make sure you know the correct order to subtract in. For example, when it says "subtract 6 from 13", it means taking away 6 from 13, or $13 - 6$, which would be 7

Application of Subtraction:

• Normally, subtraction is used to figure out times, distances, and many more real-world scenarios. Subtraction can be used in many different ways, but no matter what, having a good understanding of subtraction can help tackle any problem.

• For example, if Sara had 5 bags of candy and her friend ate 3 bags, how many bags would be left for Sara to enjoy? To solve this, you would set up an easy subtraction problem, $5 - 3$, then you would solve it. Once you solve it you should get 2 bags!

Complex Subtraction:

• Complex subtraction means many different things! It can mean decimal or fractional subtraction, subtraction involving larger numbers, and/or word problems

• Luckily, the concept of subtraction will never change even while doing complex problems. So, if you're able to get good fundamentals, you can do any subtraction problem!

• Some example problems are:

  • $1/2 - 3/8$

  • $0.54 - 1.62$

  • And many more you will see later on!

Links to resources, videos, and worksheets:

• The Story of Mathematics (Website)

• Math Is Fun (Website)

• Math Is Fun (Worksheets)

The components of subtraction!

Lesson Complete!