1)90,09-(87,44-(12,85+3,9)-0,981)=20,381~20 12,85+3,9=16,75 87,44-16,75=70,69 70,69-0,981=69,709 90,09-69,709=20,381 2)5,53+(9,7-(8,93+0,748))-5,4813=0,0707~0 8,93+0,748=9,678 9,7-9,678=0,022 5,53+0,022=5,552 5,552-5,4813=0,0707