计算(能简便的必须简算) 91×1/17+9÷17−1÷17×100 0.38×7−19/50+4×19/50 2100÷[56×(3/7−3/8)] [(2/3−1/4)÷5/6+1/2]×3/4.

问题描述:

计算(能简便的必须简算)

91×
1
17
+9÷17−1÷17×100
0.38×7−
19
50
+4×
19
50
2100÷[56×(
3
7
3
8
)]
[(
2
3
1
4
5
6
+
1
2
3
4


(1)91×

1
17
+9÷17−1÷17×100,
=91×
1
17
+9×
1
17
-
1
17
×100,
=(91+9-100)×
1
17

=0×
1
17

=0;
(2)0.38×7−
19
50
+4×
19
50

=0.38×7-0.38+4×0.38,
=0.38×(7-1+4),
=0.38×10,
=3.8;
(3)2100÷[56×(
3
7
3
8
)]

=2100÷[56×
3
7
-56×
3
8
],
=2100÷[24-21],
=2100÷3,
=700;
(4)[(
2
3
1
4
5
6
+
1
2
3
4

=[
5
12
÷
5
6
+
1
2
3
4

=[
5
12
×
6
5
+
1
2
3
4

=[
1
2
+
1
2
3
4

=1×
3
4

=
3
4