30
-
20
=
____________________
70
-
20
=
____________________
60
-
20
=
____________________
40
-
20
=
____________________
50
-
40
=
____________________
70
-
40
=
____________________
40
-
10
=
____________________
60
-
30
=
____________________
80
-
70
=
____________________
80
-
10
=
____________________
50
-
50
=
____________________
90
-
30
=
____________________
60
-
20
=
____________________
60
-
50
=
____________________
90
-
50
=
____________________
