Ответ:1. 3/16 - 5/12 = 9/48 - 20/48 = -11/48.2. 33/64 : (-11/48) = 33/64 * (-48/11) = (33 * -48) / (64 * 11) = -3 * 3 / 4 = -9/4.3. 3 * 1/12 = 3/12 = 1/4.4. -9/4 + 1/4 = -8/4 = -2.