Lesson 8
Octal Arithmetic
The sum gets a bonus
Page 270
You are correct. Here is the calculation, showing the carries explicitly:
1
1
← carries
3
5
38
4
6
28
1,
0
3
5
To give you more practice in this, here are three sets of octal additions to check. Which set contains a mistake?
1
3
28
2
0
78
6
4
28
+
2
1
78
+
7
0
28
+
2
4
68
3
5
18
1,
1
1
18
1,
1
1
08
⎫⎪⎬⎪⎭This set contains a mistake.
6
5
38
2
7
18
2
3
68
+
1
2
58
+
1
1
78
+
7
6
48
1,
0
0
08
4
0
08
1,
2
2
28
⎫⎪⎬⎪⎭This set contains a mistake.
7
6
58
2
7
38
4,
3
2
18
+
7
7
28
+
6
6
68
+
4,
4
4
48
1,
7
5
78
1,
1
6
18
1
0,
7
6
58
⎫⎪⎬⎪⎭This set contains a mistake.
