Question

直接寫得數(shù)． 3 4 ×8=	5 7 ×14=	7 12 ×10=	2 9 ×15=
5× 2 15 =	36× 5 8 =	27× 5 12 =	100× 13 25 =
7 8 ×5=	1 6 ×4=	9× 7 12 =	15× 2 15 =

Answer 1

分析：根據(jù)分?jǐn)?shù)乘整數(shù)的計(jì)算法則：分?jǐn)?shù)乘整數(shù)，用分?jǐn)?shù)的分子和整數(shù)相乘的積作分子，分母不變；及分?jǐn)?shù)乘分?jǐn)?shù)的計(jì)算法則：分?jǐn)?shù)乘分?jǐn)?shù)，用分子相乘的積作分子，分母相乘的積作分母，計(jì)算中能約分的，先約分，再計(jì)算．

解答：

解： 3 4 ×8=6	5 7 ×14=10	7 12 ×10=5 5 6	2 9 ×15=3 1 3
5× 2 15 = 2 3	36× 5 8 =22.5	27× 5 12 =11 1 4	100× 13 25 =52
7 8 ×5=4 3 8	1 6 ×4= 2 3	9× 7 12 =5 1 4	15× 2 15 =2

點(diǎn)評(píng)：此題考查了分?jǐn)?shù)乘整數(shù)的計(jì)算法則和分?jǐn)?shù)乘分?jǐn)?shù)的計(jì)算法則，應(yīng)靈活掌握和應(yīng)用．