1/13:(12/26-5/13-1/5)
1/13:(12/26-5/13-1/5)=-5/8
1) 12/26 - 5/13 = 12/26 - 10/26 = 2/26 = 1/13 2) 1/13 - 1/5 = 5/65 - 13/65 = - 8/65 3) 1/13 : ( - 8/65 ) = - 5/8 Ответ ( - 5/8 )