1) 11/21-3/35= 2)19/60-8/45= 3)3/20-2/25+1/30=
1) 11/21 - 3/35 = 55/105 - 9/105 = 46/105 2) 19/60 - 8/45 = 57/180 - 32/180 = 25/180 = 5/36 3) 3/20 - 2/25 + 1/30 = 45/300 - 24/300 + 10/300 = 31/300