题目内容
计算(1)(﹣5
)×(+1
)×(﹣2
);
(2)36×(
);
(3)用简便方法计算25×(
)2﹣(﹣25)×(
)+25×
;
(2)36×(
(3)用简便方法计算25×(
解:(1)(﹣5
)×(+1
)×(﹣2
)
=
=22;
(2)36×(
)
=36×
﹣36×
+36×
=24﹣20+21
=25;
(3)原式=25×
+25×
+25×
=25×(
+
+
)
=30.
=
=22;
(2)36×(
=36×
=24﹣20+21
=25;
(3)原式=25×
=25×(
=30.
练习册系列答案
相关题目