a) 1.(12/25 / 4/5)= 3/5 / 9/35= 7/3
b) 1.(4/5 / 9/35)=28/9 / 12/25= 175/27
c) 1. (25/36 / 7/16)= 100/63 2. 60/49 / 162/ 7= 10/189 3. 100/63 / 10/189 = 30
d) 1. (11/12 / 13/18) = 33/26 2. 33/26 / 22/33= 99/52
e) 1. (19/45 / 7/30) =38/21 2. 38/21 / 19/21 = 2
f) 1. (13/12 / 7/15) =65/28 2/ 65/28 / 39/70 = 25/6
Succes