the reciprocal of 5/3 is 3/5
5 would have to be the constant, because in algebraic terms, a constant is a term that contains only numbers and no variables, which would knock 2x right out of the question. Hope I helped.
The greatest common fact is 6.
18 ÷ 6 = 3
24 ÷ 6 = 4
In simplest form, 18/24 = 3/4