问题 解答题
简便计算.
3.2×12.5×2.5
3.7×99+3.7
3
8
×
7
4
-
3
4
×
3
8
+
3
8
答案

①3.2×12.5×2.5

=(0.8×12.5)×(4×2.5)

=10×10

=100;

②3.7×99+3.7

=3.7×(99+1)

=3.7×100

=370;

3
8
×
7
4
-
3
4
×
3
8
+
3
8

=

3
8
×(
7
4
-
3
4
+1)

=

3
8
×2

=

3
4

单项选择题
单项选择题