Which statement is true about the sum of two rational numbers?

A rational number can be written as a fraction of integers with a nonzero denominator. Adding two rational numbers keeps the result in that form: for example, a/b + c/d = (ad + bc)/bd. So the sum can always be written as a fraction. The other statements are false because rational numbers may have terminating decimals, such as 1/2 = 0.5.

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