Fractions and Least Common Multiples

The video tutorial explains how to compare two fractions, 21/28 and 6/9, using different methods. It begins by discussing the importance of having a common denominator and suggests simplifying the fractions first. The fractions are simplified to 3/4 and 2/3, making it easier to find a common denominator of 12. The tutorial then compares the fractions by converting them to have the same denominator, concluding that 21/28 is greater than 6/9. An alternative method is also demonstrated, showing how to find a common denominator without simplifying first.

What is the first step suggested for comparing two fractions?

• Multiply the fractions

• Convert to decimals

• Find a common denominator

• Find a common numerator

What is the simplified form of the fraction 21/28?

• 5/7

• 3/4

• 7/9

• 2/3

Which number is the least common multiple of 4 and 3?

• 6

• 9

• 12

• 15

What is the equivalent fraction of 3/4 with a denominator of 12?

• 8/12

• 10/12

• 6/12

• 9/12

Which fraction is greater: 9/12 or 8/12?

• 9/12

• 8/12

• Cannot be determined

• They are equal

What is the prime factorization of 28?

• 2 x 3 x 7

• 3 x 9

• 2 x 2 x 7

• 2 x 14

What is the least common multiple of 28 and 9?

• 36

• 126

• 84

• 252

How do you convert 21/28 to have a denominator of 252?

• Multiply numerator and denominator by 7

• Multiply numerator and denominator by 12

• Multiply numerator and denominator by 28

• Multiply numerator and denominator by 9

What is the result of multiplying 6 by 28?

• 148

• 188

• 208

• 168

Which method was used to find the common denominator in the alternative approach?

• Using decimals

• Direct multiplication

• Cross-multiplication

• Simplifying first