Odpowiedź:
a. 3 2/15 - 5/6 = 3 4/30 - 25/30 = 3 - 21/30 = 2 9/30 = 2 3/10 B
b. 2 9/35 - 1 5/14 = 2 18/70 - 1 25/70 = 1 18/70 - 25/70 = 1 - 7/70 = 69/70 = 9/10 D
