Question

If a=4q+r, then what are the possible values of r.

Answer 1

euclid's divsion lemma states that given 2 integers a and b, there exists unique whole numbers q and r such that
                         a = b * q + r where 0=< r <b
given equation is a = 4 * q + r
therefore possible values of r are 0 , 1, 2 or 3