Common Denominators

Front

What is a common denominator?

Back

A common denominator is a number that is a multiple of the denominators of two or more fractions. It allows fractions to be added or subtracted.

Front

What is the least common multiple (LCM)?

Back

The least common multiple (LCM) is the smallest multiple that two or more numbers share. It is often used to find a common denominator.

Front

How do you find the LCM of 3 and 8?

Back

List the multiples of each number: Multiples of 3: 3, 6, 9, 12, 15, 18, 21, 24... Multiples of 8: 8, 16, 24, 32... The LCM is 24.

Front

How do you find the LCM of 5 and 3?

Back

List the multiples of each number: Multiples of 5: 5, 10, 15, 20, 25... Multiples of 3: 3, 6, 9, 12, 15... The LCM is 15.

Front

What is the common denominator for 1/4 and 1/6?

Back

The common denominator is 12.

Front

What is the common denominator for 3/8 and 2/7?

Back

The common denominator is 56.

Front

What is the common denominator for 2/5 and 5/16?

Back

The common denominator is 80.

Front

How do you add fractions with different denominators?

Back

Find a common denominator, convert the fractions, and then add the numerators.

Front

How do you subtract fractions with different denominators?

Back

Find a common denominator, convert the fractions, and then subtract the numerators.

Front

What is the common denominator for 1/3 and 3/8?

Back

The common denominator is 24.