1)
15/27 и 24/42 =
=5/9 и 4/7 =
=(5*7)/63 и (4*9)/63 =
= 35/63 и 36/63
2) 15/54 и 28/48 =
5/18 и 7/12=
= (5*2)/36 и (7*3)/36 =
=10/36 и 21/36