(1,25+ 1 7/8):(-1 1/12-0,5)

( 1,25 + 1 7/8) : ( -1 1/12 - 0,5 ) = - 1/4.

(1 1/4+ 1 7/8) :( - 13/12 -1/2)  = (5/4 + 15/8):( -13/12 - 6/12) =( (10+15)/8 ): ((-13-6)/12) = (25/8): (-19/12) = - 25/8 *12/19 = -25* 12 / 8*19 = -75/38 = - 1 целая 37/38