Finding the Rule for Input Output

Find the Rule In Input Output Tables

Today we will look at objective

4.5B Represent problems using an input

output table and numerical expressions to generate a number pattern that follows a given rule representing the relationship of the values in the resulting sequence and their position in the sequence.

Why is this important to learn how to use input and output tables?

Because an input output table is a table that shows the relationship between sets of numbers that always follow the same rule.

Today we will use the input output table to find the rule.

To complete an input output table you need to find the rule.

• To help find the rule look for two things.

• 1. If the numbers in the in/out sections increase, you will multiply or add.

• In this case the numbers increase

So when we look at the chart, we see that going from the number in the input to the number in the output we have an increase.

• 2 increases to 8: 6 to 12 and 8 to 14

Multiple Choice

CFU

In an input output table, if numbers increase in the in/out sections you will

• add or divide

• add or subtract

• add or multiply

• multiply and divide

Our answer is add or multiply

Multiple Choice

What operations can be used to find the rule?

• addition and subtraction only when they apply

• multiplication and division only when they apply

• only addition when it applies

• all operation can be used when they apply.

Our answer choice is

All operations can be used when they apply.

To find the rule sometimes you need to add, subtract, multiply or divide or you may need to use a combination of operations.

Lets look at a short video that explains how this type of input output table works

Click on the video to hear the information.

Now lets look at an input output chart where the in/out numbers decrease

When we look at this chart, we see that the numbers in the in/out section decrease

• 12 decreases to 10

• 16 decreases to 14

• 20 decreases to 18

Multiple Choice

CFU

When the numbers in the in/out section of the chart show a decrease between numbers we would

• multiply or divide to find the rule

• subtract or divide to find the rule

• add or subtract to find the rule

• add or multiply to find the rule

Our answer is subtract or divide.

Lets look at another video that shows how this table works.

Click on the video to hear the information.

Multiple Choice

Exit ticket

What is the rule?

• - 3

• x 3

• $$\div$$ 3

• + 3

Multiple Choice

Exit Ticket 2

What is the rule

• - 2

• - 4

• + 3

• + 2

Multiple Choice

Exit Ticket Bonus

Which of the following represents the rule?

• $$\div$$ 12

• + 12

• - 12

• x 12