Fraction Simplest Form by Greatest Common Factor
Students will be able to simplify fractions using the greatest common factor between numerators and denominators.
- Write the following fraction on the board: 2436/3325
- Ask your students to turn and tell their neighbor a strategy to reduce the fraction to its "simplest form," but don’t clarify the term yet!
- Allow students to share their ideas with the whole class or with a partner. Note related academic terminology for future reference.
- Reveal that today’s lesson is about simplifying fractions with larger numerator and denominators by using their greatest common factor. Explain that simplest form is when a fraction’s numerator and denominator can no longer be divided evenly by a common factor.
Explicit Instruction/Teacher modeling(10 minutes)
- Hand out and lead your class through the opening model of the Equivalent Fractions and Greatest Common Factor worksheet.
- Answer any clarifying questions.
Guided Practice(10 minutes)
- Lead your class through exercise #1.
- Guide your students through exercise #2, with students reading and offering explanations for as many next steps as possible.
Independent working time(15 minutes)
- Release your students to complete the remaining exercises on the worksheet independently.
- For students needing more practice factoring, have them complete the Greatest Common Factor: Easy worksheet noted in the references section of this lesson plan.
- Share the strategy for finding if a number is divisible by three. If the sum of the digits are divisible by three, the face value of the number is divisible by three.
- For example: 363 is divisible by 3, because 3 + 6 + 3 = 12, and 12 is divisible by 3 (12 = 3 x 4).
- Have students make up fractions with:
- Numerators and denominators with three to four digits
- Divisible by three
- A solution for simplest form
- Powerpoint and Keynote are great slide show applications for presenting processes one step at a time.
- Show your students a fraction with a single-digit numerator and denominator.
- Then have them lead you through to an equivalent fraction with a three-digit numerator and denominator.
Review and closing(10 minutes)
- Allow your students to share out answers whole class.
- Discuss: What can simplified fractions tell us about equivalent forms with larger numerators and denominators?