Ответ:а) 5/9 · 1/5 = 1/9.б) 4/7 · 1/4 = 1/7.в) 1 · 13/5 = 13/5 = 2 3/5.г) 7 · 7/4 = 49/4 = 12 1/4.д) 9 · 7/3 = 21.е) 4 · 9/8 = 9/2 = 4 1/2.