Week 5, Day 3 – Wednesday October 10, 2012

Warm Up:Use long division to find the decimal expansion of each number below. For example, to write the decimal expansion of , divide 7 by 11. a.) b.) c.)

Which are decimals that repeat? Circle them.

Homework #19: “Prime or Composite?” Worksheet and “Exploring Divisibility” Worksheet {Front and Back} *Note: Last chance to take online practice test

Week 5, Day 3 – Wednesday October 10, 2012

Warm Up Answer:

Homework #19: “Prime or Composite?” Worksheet and “Exploring Divisibility” Worksheet {Front and Back}

Goals for Today • Hands-On Lab: Explore Rational Numbers

Vocabulary:- Terminating decimal- Repeating decimal- Rational number

Week 5, Day 3 – Wednesday October 10, 2012

California Common Core StandardThe Number System 2d: Convert a rational number to a decimal using long division; know that the decimal form of a rational number terminates in 0s or eventually repeats.

Activity 1: #1. Find the decimal expansion of each rational number

• Guided Example #1:

• Guided Example #2:

Activity 1: #1. Find decimal expansion of each rational number

• Now you try in partners! Use scratch paper.

Activity 1:

#2. Write each rational number and its decimal expansion on an index card as shown below.

Activity 1: #3. Make Piles

Terminating Repeating

Neither

Activity 1: #4. Which rational numbers are in each stack? List the rational number in the correct column below.

Terminating Repeating Neither

1. When you use long division to write a decimal expansion, how can you tell that the decimal terminates? How can you tell that the decimal repeats?

If the division ends or terminates, because the remainder is zero, then the decimal is a terminating decimal. If the division leads to a repeating block of one or more digits (where all digits are not zeros) after the decimal point, then the decimal is a repeating decimal.

Week 5, Day 3 – Wednesday October 10, 2012

Activity 1: Think and Discuss

Activity 1: Think and Discuss2. What do you notice about your stacks of index cards? Are there any cards in the stack for decimals that neither terminate nor repeat?

• There are no cards in the stack for decimals that neither terminate nor repeat.

3. What can you say about the decimal expansion of any rational number?

• The decimal expansion of any rational number either terminates or repeats.

Week 5, Day 3 – Wednesday October 10, 2012

Rational Number

• Let’s revisit the original question: What is a rational number?

• What are examples of numbers that are not rational?