①1- -
② + -
③ + + +
④0.75× ×
⑤( + - )÷
⑥ × ÷ ×
÷ =
× =
1﹣ =
×6=
15÷ =
﹣ =
+ =
+ =
﹣ =
+ + =
1﹣ =
1﹣ ﹣ =
①-+
②+(+)
③7-(-)
④
⑤
⑥
12和18 9和27 12和11