a) 2/3 + 1/3 • 4/5 - 3/5 = 2/3 + 4/15 - 3/5 = 10/15 + 4/15 - 9/15 = 5/15 = 1/3
b) 2,9 - 0,9 • 4 : 3 = 2,9 - 3,6 : 3 = 2,9 - 1,2 = 1,7
c) 2,3 + 0,7/0,7 • 14/15 = 2,3 + 1 • 14/15 = 2 3/10 + 14/15 = 2 9/30 + 28/30 = 2 37/30 = 3 7/30
d) (4/15 - 1,15) : 1 7/18 = (4/15 - 1 15/100): 1 7/18 = (80/300 - 1 45/300) : 1 7/18 = (80/300 - 345/300) : 1 7/18 = (- 265) : 25/18 = (-265) • 18/25 =(-53) • 18/5 = - 954/5 = - 190 4/5
