4,45-12-4ц1/6+7,9+1ц2/3-2,36=4,45+7,9-12-4ц1/6+1ц4/6=12,35-12-3ц7/6+1ц4/6=0,35-(3ц7/6-1ц4/6)=0,35-2ц3/6=0,35-2,5=-2,15