Question 1111997
Assume a,b,c,d are integers and {{{b<>0}}} and {{{d<>0}}},
{{{a/b+c/d=(a/b)(d/d)+(c/d)(b/b)}}}
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{{{a/b+c/d=(ad/bd)+(bc/bd)}}}
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{{{a/b+c/d=((ad+bc))/bd)}}}