1. -6 3/14 - 1 6/7 = - (6 3/14 + 1 6/7) = - (6 3/14 + 1 12/14) = -(6 + 1 + 3/14 + 12/14) = -(7 + 15/14) = -(7 + 1 1/14) = -(7 + 1 + 1/14) = -(8 + 1/14) = -8 1/14