MathIsimple

Lesson 3-3: Patterns & Functions

Understand number patterns and simple functions using input-output tables!

Learning Scenario: Number Patterns

Scenario: You're helping organize a school fundraiser. For every 2 tickets sold, the school earns $5. Let's create a pattern to see how much money is earned for different numbers of tickets.

What We Need to Find:

  • • Pattern for money earned
  • • 2 tickets = $5
  • • 4 tickets = $10
  • • 6 tickets = $15

Tools We'll Use:

  • • Input-output tables
  • • Function rules
  • • Pattern recognition
  • • Real-world applications

Understanding Patterns

What is a Pattern?

A pattern is a sequence of numbers that follows a specific rule. Once you find the rule, you can predict what comes next in the sequence.

2, 4, 6, 8, 10, 12, ...

This pattern adds 2 each time

Finding the Rule

Look at how the numbers change from one to the next

Using the Rule

Apply the same rule to find the next numbers

Input-Output Tables

Creating Our Table

Let's create an input-output table for our fundraiser scenario:

Input (Tickets)Output (Money Earned)
2$5
4$10
6$15
8$20
10$25

Input

The number of tickets sold (what goes in)

Output

The money earned (what comes out)

Finding Function Rules

Step 1: Look for the Pattern

Let's analyze our table to find the rule:

2 tickets → $5

$5 ÷ 2 = $2.50 per ticket

4 tickets → $10

$10 ÷ 4 = $2.50 per ticket

6 tickets → $15

$15 ÷ 6 = $2.50 per ticket

Pattern Found: Each ticket earns $2.50!

Step 2: Write the Function Rule

Now we can write a rule to find the money earned for any number of tickets:

Money Earned = 2.5 × Number of Tickets

Function rule

Or: y = 2.5x

Where x = tickets, y = money

Using the Function

Example: Find Money for 12 Tickets

Let's use our function rule to find how much money is earned for 12 tickets:

y = 2.5x

Our function rule

y = 2.5 × 12

Substitute x = 12

y = $30

12 tickets earn $30!

Practice Problems

Problem 1: Book Club

A book club charges $3 per person for each meeting. Complete the table and find the function rule.

People (x)Cost (y)
1$3
2$6
3$9
4$12

Function Rule: y = 3x

Cost = $3 × number of people

Problem 2: More Patterns

Find the next 3 numbers: 5, 10, 15, 20, __, __, __

25, 30, 35

Rule: Add 5 each time

Find the next 3 numbers: 2, 4, 8, 16, __, __, __

32, 64, 128

Rule: Multiply by 2 each time

Key Takeaways

Patterns & Functions

  • Patterns follow specific rules
  • Input-output tables show relationships
  • Function rules help predict outputs
  • Look for consistent changes

Remember

  • Input is what goes in, output is what comes out
  • Test your rule with different inputs
  • Use real-world examples to understand
  • Practice with different types of patterns