Bonjour
a. 3/7 x 8/3 = 24/21 = (3 x 8) / (3 x 7) = 8/7
b. 2/15 x 15/11 = 30/165 = (15 x 2) / (15 x 11) = 2/11
c. 14/23 x 1/7 = 14/161 = (7 x 2) / (7 x 23) = 2/23
d. 2/11 x 3/4 = 6/44 = (2 x 3) / (2 x 22) = 3/22
e. 7/8 x 1/21 = 7/168 = (7 x 1) / (7 x 24) = 1/24
f. 2/3x 3/4 x 4/5 = 6/12 x 4/5 = 24/60 = (12 x 2) / (12 x 5) = 2/5.
