① 12×
2
3 =8, ②1-54%=0.46, ③
2
5 ÷
2
5 =1, ④ 0.5+
1
4 =0.75, ⑤
3
8 ×
4
21 =
1
14 ,
⑥
8
9 ÷4 =
2
9 , ⑦ 7+
5
9 =7
5
9 , ⑧ 3.5÷
1
2 =7, ⑨
3
5 ÷
6
5 =
1
2 , ⑩
2
5 +
5
6 -0.4 =
5
6 .
① 12×
2
3 =8, ②1-54%=0.46, ③
2
5 ÷
2
5 =1, ④ 0.5+
1
4 =0.75, ⑤
3
8 ×
4
21 =
1
14 ,
⑥
8
9 ÷4 =
2
9 , ⑦ 7+
5
9 =7
5
9 , ⑧ 3.5÷
1
2 =7, ⑨
3
5 ÷
6
5 =
1
2 , ⑩
2
5 +
5
6 -0.4 =
5
6 .