umidmavlonov5 12.36(1.39+1.11)-2.5*4.36

eloyanj 1)12,36*1,39=17,1804; 2)1,11*12,36=13,7196; 3)2,5*4,36=10,9; 4)17,1804+13,7196=30,9; 5)30,9-10,9=20.