Bonsoir,
a. 6/5 x 11/4 = 66/20 = (2 x 33) / (2 x 10) = 33/10.
b. - 9/5 x 7/6 = - 63/30 = (3 x - 21) / (3 x 10) = - 21/10
c. - 10/9 x - 7/15 = 70/135 = (5 x 14) / (5 x 27) = 14/27.
