An equation is show. 30/100 +b= 7/10

Divide the numbers
3
0
1
0
0
+

=
7
1
0
30
100
+
b
=
7
10
10030+b=107
3
1
0
+

=
7
1
0
3
10
+
b
=
7
10
103+b=107
2
Rearrange terms
3
1
0
+

=
7
1
0
3
10
+
b
=
7
10
103+b=107

+
3
1
0
=
7
1
0
b
+
3
10
=
7
10
b+103=107
3
Subtract
3
1
0
3
10
103
from both sides of the equation

+
3
1
0
=
7
1
0
b
+
3
10
=
7
10
b+103=107

+
3
1
0
−
3
1
0
=
7
1
0
−
3
1
0
b
+
3
10
−
3
10
=
7
10
−
3
10
b+103−103=107−103
4
Simplify
Subtract the numbers
Subtract the numbers
again

=
2
5
b
=
2
5
b=52
Solution

=
2
5
b

Main idea on left, details on right