数学北师大版四年级下册手拉手期末复习x

手拉手复习练习题1.把左右两边相等的式子用线连起来。(5+8)×0.4(8+0.8)×1.258.8×1.255.8+(3.67+0.33)3.6×4×2.5(1.25×8)×2.63.67+5.8+0.335×0.4+8×0.41.25×2.6×83.6×(4×2.5) 2.用简便方法计算下面各题。2.5×(3.8×0.4)=2.5×0.4×3.8=1×0.8=0.8a×(b×c)=a×c×b 7.69×101=7.67×（100+1）=7.67×100+7.67×1=767+7.67=774.67(a+b)×c=a×c+b×c 8.36-2.48-3.52=8.36-(2.48+3.52)=8.36-6=2.36a-b-c=a-(b+c) 46×0.33+54×0.33=(46+54)×0.33=100×0.33=33a×c+b×c=(a+b)×c 0.25×99+0.25=0.25×99+0.25×1=0.25×(99+1)=0.25×100=25a×c+b×c=(a+b)×c 0.125×72=0.125×8×9=1×9=9a×b×c=a×c×b（8×9=72） 3.数学诊所。13+87×0.5=100×0.5=5013+87×0.5=13+43.5=56.5 0.4×8.7×2.5=（0.4×2.5）×8.7=10×8.7=8.70.4×8.7×2.5=（0.4×2.5）×8.7=1×8.7=8.7 6.根据运算定律填空。59×2.5×0.4=（）×（）×（）0.8×125+.2×15=（+）×152×1.25×5×8=（×）×（×）9.63×2.5+9.63×7.5=9.63×（+）（）×0.8+5×（）=（+39.2)×50.63×99+0.63=（+）×（）2.50.4590.82.2251.2582.57.539.250.89910.63