7/12 - 2/7 + 1/12 = 7/12 - 1/12 + 2/7 = 1/2 + 2/7 = 11/14
7/12 - 2/7 + 1/12 = 7/12 + 1/12 - 2/7 = 2/3 - 2/7 = 14/21 - 6/21 = 12/21 = 4/7
\(\frac{7}{12}\)\(+\)\(\frac{1}{12}\)\(-\)\(\frac{2}{7}\)\(=\)\(\frac{2}{3}\)\(-\)\(\frac{2}{7}\)\(=\)\(\frac{14}{21}\)\(-\)\(\frac{6}{21}\)\(=\)\(\frac{12}{21}\)\(=\)\(\frac{4}{7}\)