<span>The rule of signs is the same for multiplication and division.
Two numbers with the same sign, multiplied or divided, the answer is positive.
Two numbers with different signs, multiplied or divided, the answer is negative. </span>
16.454 is greater than 16.45.
I agree with your answer "supplementary". The two angles combine to form 180 degrees, aka a straight angle
Your teacher seemed to have made a typo.