(4,3+2,4:8)×3 280,8:12-0,3×24 (17,6×13-41,6):12
(4,3+2,4:8)×3= (4.3+0.3)*3=4.6*3=13.8 280,8:12-0,3×24=23.4-7.2=16.2 (17,6×13-41,6):12=(228.8-41.6):11=187.2:12=15.6