



 
Hi Fathia, The definition of a rational number is any number that can be expressed as the ratio of two integers that have no common factors (i.e. a fraction in lowest terms) and the denominator is not zero. Thus, if a is a rational number, there must exist some w and x which are integers, where x is not equal to zero and in which a = w/x. Furthermore, w and x have no common factors (besides +/1 of course) and Use this starting point to determine what this says about b. Then use w, x and the variables you use for describing the value of b to make observations and reasoned conclusions about the sum of the two fractions. Hope this helps,  


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