Bonjour,
1)
a. 3/4 x 4/5 = 12/20 = (4 x 3) / (4 x 5) = 3/5
b. 5/7 x 3/5 = 15/35 = (5 x 3) / (5 x 7) = 3/7
c. 2/3 x 3/2 = 6/6 = 1
2)
a. - 2/9 x - 3/5 = 6/45 = (3 x 2) / (3 x 15) = 2/15
b. 1/- 6 x 2/9 = - 2/54 = (2 x - 1) / (2 x 27) = - 1/27
c. - 4/11 x 22/3 = - 88/33 = (11 x - 8) / (11 x 3) = - 8/3.
