(-4/5-4/7)*(5 7/9-7 11/12)

-4/5-4/7=-28/35-20-35=-48/355 7/9-7 11/12=52/9-95/12=208/36-285/36= -77/36-48/35 * -77/36= 48*77/35*36=4*11/5*3=44/15=2 14/15Ответ: 2 14/15