выполни умножение дробей
1. 19/42*21/38=
2.24/66*39/40=
3. 25/36*51/70=
4. 7/16*8/49=
5. 4/7*8/9=
6. 56/69*69/77=
7. 39/86*43/78=
9. 50/65*40/75=
8. 8/25*5/56=
9. 29/69*23/58=
10. 88/93*63/77=
11. 27/64*56/57=
12. 5/9*7/8=