第五单元自主检测 1. 0.5 0.3 3.9 0.48 0.021 8 40 0.6 2. 3. (1) 0.25x1.58x4 =0.25×4x1.58 =1×1.58 =1.58 (2) 78.5x0.8-8.5x0.8 =0.8x(78.5-8.5) =0.8x70 =56 (3) 99x1.24+1.24 =1.24x(99+1) =1.24x100 =124 (4) 4.35+0.17+0.65+0.83 =(4.35+0.65)+(0.17+0.83) =5+1 =6 (5) 3.6÷[0.25x(17.3+30.7)] =3.6÷[0.25×4x12] =3.6÷12 =0.3 4. (1) A (2) B (3) C (4) C |