Applying GCF and LCM in Fraction Operations

This lesson covers the application of Greatest Common Factor (GCF) and Least Common Multiple (LCM) in fraction operations, focusing on multiplication, simplification, and addition/subtraction of fractions. It explains two methods for simplifying products of fractions, demonstrates multiplying fractions by whole numbers, and discusses using LCM for adding and subtracting fractions. The lesson also includes practical examples to illustrate these concepts.

What is the first step in multiplying two fractions?

• Divide the numerators and denominators

• Subtract the numerators and denominators

• Multiply the numerators together and the denominators together

• Add the numerators and denominators

How can you simplify the product of two fractions?

• By subtracting the numerators and denominators

• By dividing both the numerator and denominator by their GCF

• By multiplying the numerators and denominators

• By adding the numerators and denominators

In Method B of simplifying fractions, when can you cancel out common factors?

• When a numerator and a denominator share a common GCF

• When the fractions are already in simplest form

• When both numerators share a common GCF

• When both denominators share a common GCF

What is the result of multiplying 1/5 by 2/3?

• 1/15

• 2/5

• 2/15

• 1/3

How do you multiply a fraction by a whole number?

• Rewrite the whole number as a fraction over one and then multiply

• Add the whole number to the fraction

• Subtract the whole number from the fraction

• Divide the fraction by the whole number

If 5/9 of 18 students have pets, how many students have pets?

• 8

• 9

• 10

• 11

Why do we need to find the LCM when adding or subtracting fractions?

• To find a common numerator

• To find a common denominator

• To simplify the fractions

• To multiply the fractions

What is the LCM of 15 and 6?

• 45

• 60

• 30

• 15

What is the simplified form of 22/42?

• 11/21

• 10/20

• 10/21

• 11/20

What does the word 'of' mean in math?

• Add

• Subtract

• Multiply

• Divide