问题
解答题
用简便方法计算: 3
12×2
(
|
答案
①3
×5 12
+4 9
×35 9 5 12
=3
×(5 12
+4 9
)5 9
=3
×15 12
=3
;5 12
②12×23 4
=12×11 4
=33;
③(
+2 9
)×272 27
=
×27+2 9
×272 27
=6+2
=8.
用简便方法计算: 3
12×2
(
|
①3
×5 12
+4 9
×35 9 5 12
=3
×(5 12
+4 9
)5 9
=3
×15 12
=3
;5 12
②12×23 4
=12×11 4
=33;
③(
+2 9
)×272 27
=
×27+2 9
×272 27
=6+2
=8.