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Sometimes fractions have different denominators. These are called unlike fractions. When adding or subtracting fractions with unlike denominators, it is necessary to find a common denominator to get the correct answer. This is the same process as finding the least common multiple.

Example 1/30 + 1/42

Factor them.

2 x 3 x 5 = 30

2 x 3 x 7 = 42

Combine the factors, eliminating duplicates.

2 x 3 x 5 x 7 = 210, the lowest common denominator.

Q: What is a common denominator?

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The least common denominator is the least common multiple of the denominators of the fractions.

A common denominator is needed when adding or subtracting fractions of different denominators.

They are essentially the same. A common denominator is the common multiple of a set of denominators of a set of fractions.

You need at least two numbers to find a common denominator.

It is infinity but the lowest common denominator is 3185

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A common denominator is 7.A common denominator is 7.A common denominator is 7.A common denominator is 7.

That's the least common denominator or LCD.

The least common denominator.

A few synonyms for common denominator are , common divisor, common measure, denominator, numerator

There can be no greatest common denominator. For supose x is the greatest common denominator. ie 24 divides x and 36 divides x. Then 2x is a common denominator and 2x > x so 2x is a greater common denominator than the greatest common denominator. That contradiction implies that there is no greatest common denominator.

A common denominator of 20 and 30 is 600. This is NOT the least common denominator, though.

The greatest common denominator is infinite. The least common denominator is 45.

A common denominator, though not the least, is 80.

You Ned to find a larger common denominator or multiply the denominators to gain a common denominator.

A common denominator is 84.

The least common denominator is 222.

A common denominator is 84.