(1)
4
5 +
11
15 +
3
10 ,
=
23
15 +
3
10 ,
=1
5
6 ;
(2)60.62-(9.2+12.62),
=60.62-9.2-12.62,
=48-9.2,
=38.8;
(3)6.8+
1
6 +3.2+
5
6 ,
=(6.8+3.2)+(
1
6 +
5
6 ),
=10+1,
=11;
(4)
15
11 -
3
7 -
4
7 ,
=
15
11 -(
3
7 +
4
7 ),
=
15
11 -1,
=
4
11 ;
(5)
9
11 +
5
6 +
2
11 -
1
6 ,
=(
9
11 +
2
11 )+(
5
6 -
1
6 ),
=1+
2
3 ,
=1
2
3 ;
(6)
7
8 -(
7
10 -
1
8 ),
=
7
8 +
1
8 -
7
10 ,
=1-
7
10 ,
=
3
10 .