(2 7/15+1 7/12)•1 1/9-1 7/8
(2 7/15 + 1 7/12) * 1 1/9 - 1 7/8 = 2 5/8 1) 2 7/15 + 1 7/12 = 2 28/60 + 1 35/60 = 3 63/60 = 4 3/60 = 4 1/20 2) 4 1/20 * 1 1/9 = 81/20 * 10/9 = (9*1)/(2*1) = 9/2 = 4 1/2 3) 4 1/2 - 1 7/8 = 4 4/8 - 1 7/8 = 3 12/8 - 1 7/8 = 2 5/8