0.2+0.5=0.7, 5.2-0.8=4.4, 10-2.5=7.5,
210÷3=70, 23×100=2300,
3
7 +
3
7 =
6
7 ,
3
10 +
5
10 =
4
5 ,
9
12 -
3
12 =
1
2 ,
3
8 +
3
8 =
3
4 ,
2
5 -
1
5 =
1
5 .
0.2+0.5=0.7, 5.2-0.8=4.4, 10-2.5=7.5,
210÷3=70, 23×100=2300,
3
7 +
3
7 =
6
7 ,
3
10 +
5
10 =
4
5 ,
9
12 -
3
12 =
1
2 ,
3
8 +
3
8 =
3
4 ,
2
5 -
1
5 =
1
5 .