簡(jiǎn)便算法
250×60

630÷35÷2

125×16

800÷32
25×36 810÷54 22×6×5 55×14.
分析:(1)根據(jù)積不變規(guī)律,第一個(gè)因數(shù)乘4,第二個(gè)因數(shù)除以4,然后再計(jì)算;
(2)根據(jù)除法的性質(zhì)簡(jiǎn)算;
(3)先把16分解成8×2,再運(yùn)用乘法結(jié)合律簡(jiǎn)算;
(4)(6)根據(jù)商不變規(guī)律簡(jiǎn)算;
(5)先把36分解成4×9,再運(yùn)用乘法結(jié)合律簡(jiǎn)算;
(7)運(yùn)用乘法交換律簡(jiǎn)算;
(8)先把14分解成2×7,再運(yùn)用乘法結(jié)合律簡(jiǎn)算.
解答:解:(1)250×60,
=(250×4)×(60÷4),
=1000×15,
=15000;

(2)630÷35÷2,
=630÷(35×2),
=630÷70,
=9;

(3)125×16,
=125×8×2,
=1000×2,
=2000;

(4)800÷32,
=(800÷8)÷(32÷8),
=100÷4,
=25;

(5)25×36,
=25×4×9,
=100×9,
=900;

(6)810÷54,
=(810÷9)÷(54÷9),
=90÷6,
=15;

(7)22×6×5,
=22×5×6,
=110×6,
=660;

(8)55×14,
=55×2×7,
=110×7,
=770.
點(diǎn)評(píng):完成本題要注意分析式中數(shù)據(jù),運(yùn)用合適的簡(jiǎn)便方法計(jì)算.
練習(xí)冊(cè)系列答案
相關(guān)習(xí)題

同步練習(xí)冊(cè)答案