a) 5 * 5/9 = 25/9 = 2 i 7/9
b) 3 * 3/5 = 9/5 = 1 i 4/5
c) 3 * 5/6 = 5/2 = 2 i 1/2
d) 12 * 2/5 = 24/5 = 4 i 4/5
e) 9/10 * 8 = 9/5 * 4 = 36/5 = 7 i 1/5
f) 3/4 * 17 = 51/4 = 12 i 3/4