計算下面各題,能簡便計算的要簡便計算.
5.27-1.98-0.02        
3.2×5.7+6.8×5.7        
2.5×6.8×0.4 5.6-36÷30       
0.72+9.6÷3.2       7.75×[20÷(3.24-3.04)].
分析:①5.27-1.98-0.02,運用減法的運算性質(zhì)簡算;      
②3.2×5.7+6.8×5.7,運用乘法分配律簡算;
③2.5×6.8×0.4,運用乘法交換律和結(jié)合律簡算;
④5.6-36÷30,先算除法,再算減法;
⑤0.72+9.6÷3.2,先算除法,再算加法;
⑥7.75×[20÷(3.24-3.04)].先算小括號里面的,再算中括號里面,最后算乘法.
解答:解:①5.27-1.98-0.02   
=5.27-(1.98+0.02)
=5.27-2
=3.27;
     
②3.2×5.7+6.8×5.7
=(3.2+6.8)×5.7
=10×5.7
=57;

③2.5×6.8×0.4
=(2.5×0.4)×6.8
=1×6.8
=6.8;

④5.6-36÷30
=5.6-1.2
=4.4;

⑤0.72+9.6÷3.2
=0.72+3
=3.72;

⑥7.75×[20÷(3.24-3.04)]
=7.75×[20÷0.2]
=7.75×100
=775.
點評:此題考查的目的是理解掌握小數(shù)四則混合運算的順序及它們的計算法則,并且能夠靈活選擇簡便方法進(jìn)行計算.
練習(xí)冊系列答案
相關(guān)習(xí)題

科目:小學(xué)數(shù)學(xué) 來源: 題型:

計算下面各題(能簡便的用簡便方法計算).
10.15-10.75×0.4-5.7         
 5.8×(3.87-0.13)+4.2×3.74
32.52-(6+9.728)÷3.2×2.5
[(7.1-5.6)×0.9-1.15]÷2.5
5.4÷[2.6×(3.7-2.9)+0.62]
[20-(90.75÷6.6+2.25)]×11.6.

查看答案和解析>>

同步練習(xí)冊答案
闂傚倸鍊搁崐鐑芥嚄閼哥數浠氬┑掳鍊楁慨瀵告崲濮椻偓閻涱喛绠涘☉娆愭闂佽法鍣﹂幏锟� 闂傚倸鍊搁崐鎼佸磹閹间礁纾归柟闂寸绾捐鈹戦悩鍙夋悙缂佺媭鍨堕弻銊╂偆閸屾稑顏�