(7x+16):11+8/12=19991/19991

/-дробная черта

(7х+16):11+2/3=1(7х+16):11=1 - 2/3(7х+16):11=1/37х+16=1/3:11=1/3*1/117х+16=1/337х=1/33-167х=15 32/33х=15 32/33 : 7=15 32/33 * 1/7х=75 2/7