[(12/25−0.28)×5/13+1÷(3/4+1/3)]×119/20.

问题描述:

[(1

2
25
−0.28)×
5
13
+1÷(
3
4
+
1
3
)]×1
19
20

[(1

2
25
-0.28)×
5
13
+1÷(
3
4
+
1
3
)]×1
19
20

=[(1
2
25
+
7
25
)×
5
13
+1÷
13
12
]×1
19
20

=[
34
25
×
5
13
+
12
13
39
20

=
34
25
×
5
13
×
39
20
+
12
13
×
39
20

=
51
50
+
9
5

=
141
50