## Missing Operations (Add and Subtract)

#### Aligned To Common Core Standard:

**Grade 1 Operations** - 1.OA.B.4

How to Determine What Operations Are Missing In an Equation (Example: 4 "?" 3 = 1) Ever found yourself in a situation where you have to determine a missing operation in an equation? Well, like finding the missing terms in a sequence, there are cases where you have to determine the missing operation in an equation. So, how do you find a missing operation? You do not have to freak out as it is very easy. Here is an example that will help you grasp the concept! Example: Solve 72( ? ) 27 - 322 ÷ 14 = 1,921 Now, there are many different approaches to solving mathematical equations. A tip that will help you reach your answer is a quick and easy way is to take a reverse approach. By looking at this equation, we know that we have to divide 322 by 14, as per the order of operations. 72 ( ? ) 27 - 23 = 1,921 To further solve this, you need to add 23 to both sides of the equation; 72 ( ? ) 27 - 23 + 23 = 1,921 + 23. 72 ( ? ) 27=1,944 The final step is more of a trial and error method, and it is where you will have to use your common sense. The four basic arithmetic operations that you can use here include addition, subtraction, multiplication, and division. It is obvious that subtracting 27 from 72 will never give such a big number; also, adding these numbers will give a very small answer. The division operation will give a small number, and when you apply the multiplication operation, you will get 1944. 72 × 27 = 1,944 This selection of worksheets and lessons help students recognize missing addition and subtraction operators.

### Printable Worksheets And Lessons

- Addition or Subtraction Step-by-Step Lesson- Find which of the two signs are missing and drop it in there.
- Guided Lesson - See if you can get the gold medal. The first two make it possible.
- Guided Lesson Explanation - I give you a one sentence explanation here for the problems, but make sure to read the introduction, it will make more sense.
- Practice Worksheet - I definitely got a bit happy with the 5s and 7s.
- Matching Worksheet - Match the partial and whole problems together.

#### Guided Lessons

It is funny for as many emails I get for having cute pictures with the worksheets, I get as many emails with people against them. What do you think?

- Guided Lesson 1 - Here is where we lose a few students; horizontal operations with an integer in the teens.
- Guided Lesson 2 - We set them on a course for success here.
- Step-by-Step Lesson 1 - See if you can out fox this one.
- Step-by-Step Lesson 2 - More of the same here.
- Step-by-Step Lesson 3 - If students are having a really hard time with this skill, give them this one.

#### Practice Worksheets

These are designed to be more drill oriented.

- Independent Practice Worksheet 1- I stuck with the horizontal format to be more a challenge for them.
- Independent Practice Worksheet 2- Just another dose of problems for you.
- Matching Worksheet - You can complete this without understanding the symbol, but it is a nice way to ease into the skill.
- True/False Worksheet - These are black and white; right or wrong.