8 Sector Circle
Please note that the first 24 slides give the students some visual
help with understanding addition of fractions. You will not want to
go through all of these, perhaps only a small selection. If you wish
to skip these you can go immediately to slides 26 or 29.
1
4
1
8
2
8
2 1
8 4
1 1
8 8
1/8 + 1/8
3
8
1
2
4
8
1
4
1
8
1 1
8 4
3
8
1/8 + 1/4
2
8
3
8
1
2
4
8
1
4
1
8
1 1
4 4
3
8
1/4 + 1/4
2
8
2 1
4 2
1
2
4
8
1
4
1
8
1 1
2 8
3
8
1/2 + 1/8
2
8
5
8
1
2
4
8
1
4
1
8
1 1
2 4
3
8
1/2 + 1/4
2
8
3
4
1
2
4
8
1
4
1
8
3 1
8 4
3
8
3/8 + 1/4
2
8
5
8
1
2
4
8
1
4
1
8
3 3
8 8
3
8
3/8 + 3/8
2
8
6 3
8 4
1
2
4
8
1
4
1
8
1 3
2 8
3
8
1/2 + 3/8
2
8
7
8
1
2
4
8
8 Sector Blank
Worksheet
12 Sector Circle
1
12
1
6
2
12
1
1
2 12
1
3
1
4
3
12
7
12
4
12
1/2 + 1/12
1
2
6
12
1
12
1
6
2
12
1 1
2 6
1
3
1
4
3
12
8 2
12 3
4
12
1/2 + 1/6
1
2
6
12
1
12
1
6
2
12
1 1
2 4
1
3
1
4
3
12
9
3
12 4
4
12
1/2 + 1/4
1
2
6
12
1
12
1
6
2
12
1 1
2 3
1
3
1
4
3
12
10 5
12 6
4
12
1/2 + 1/3
1
2
6
12
1
12
1
6
1
1
3 12
1
3
2
12
1
4
3
12
5
12
4
12
1/3 + 1/12
1
2
6
12
1
12
1
6
2
12
1 1
3 6
1
3
1
4
3
12
1
2
4
12
1/3 + 1/6
1
2
6
12
1
12
1
6
2
12
1 1
3 4
1
3
1
4
3
12
7
12
4
12
1/3 + 1/4
1
2
6
12
1
12
1
6
2
12
1 1
4 6
1
3
1
4
3
12
5
12
4
12
1/4 + 1/6
1
2
6
12
1
12
1
6
1
1
4 12
1
3
2
12
1
4
3
12
4
1
12 3
4
12
1/4 + 1/12
1
2
6
12
1
12
1
6
2
12
1
1
6 12
1
3
1
4
3
12
3
1
12 4
4
12
1/6 + 1/12
1
2
6
12
12 1/6
Sector
Blank
+ 1/12
Worksheet
Addition/Subtraction of Fractions
REMEMBER:
Denominator
5
12
Numerator
Adding/subtracting fractions with the same
denominator is easy. You simply
add/subtract the numerators.
Num/Den
Adding and subtracting fractions with the
same denominator is easy. You simply
add or subtract the numerators.
Same Den
3 4
8 8
7
8
7
4
12 12
11
12
Adding/subtracting fractions with different denominators is more
complicated. You need to find the Lowest Common Multiple (LCM) of the
denominators first.
Remember: The Lowest Common Multiple of 2 or more numbers is the
smallest number that the given numbers will divide into without remainder.
Find the lowest common multiple of the following numbers:
3 and 4
5 and 20
Multiples of
3 and 4
Multiples of
5 and 20
3 and 8
Multiples of
3 and 8
3
8
6
16
9
24
3
4
5
20
12
32
6
8
10
40
15
40
9
12
15
60
18
48
12
16
20
80
21
56
15
20
25
100
24
64
12 is the LCM
20 is the LCM
LCM
24 is the LCM
2
3
1
4
+
8
12
+
=
Diagram
1
+
3
12
11
12
Multiples of
3 and 4
3
4
6
8
9
12
12
16
15
20
12 is the LCM
2
5
3
8
+
16
40
+
=
+ Diagram 2
15
40
31
40
Multiples of 5
and 8
5
8
10
16
15
32
20
40
25
48
30
56
35
64
40
72
40 is the LCM
+ Diagram 3
3
4
1
6
+
9
12
=
+
2
12
11
12
Multiples of
4 and 6
4
6
8
12
12
18
16
24
20
30
12 is the LCM
Example questions
5
1
1
8 3
2
Examples + 1
15 + 8
23
24
24
2 1
8 + 5
5 4
20
1
3
3
12 4
1 + 9
12
13
20
10 5
12 6
Example questions
Examples + 2
3
5
+
11
3
6
5
4
1
4 8
8
8
8
47
11
7
11
+
33
14
5
1
36
36
18 12
36
6
5 3
40 + 27
9 8
72
67
72
2
3
- Diagram 1
1
4
8
12
=
-
3
12
Multiples of
3 and 4
3
4
6
8
9
12
12
16
15
20
12 is the LCM
2
3
1
4
8
12
=
-
3
12
5
12
Multiples of
3 and 4
3
4
6
8
9
12
12
16
15
20
12 is the LCM
2
5
3
8
16
40
=
- Diagram 2
-
15
40
Multiples of 5
and 8
5
8
10
16
15
32
20
40
25
48
30
56
35
64
40
72
40 is the LCM
2
5
3
8
16
40
=
-
15
40
1
40
Multiples of 5
and 8
5
8
10
16
15
32
20
40
25
48
30
56
35
64
40
72
40 is the LCM
-Diagram 3
3
4
1
6
9
12
=
-
2
12
Multiples of
4 and 6
4
6
8
12
12
18
16
24
20
30
12 is the LCM
3
4
1
6
9
12
=
-
2
12
7
12
Multiples of
4 and 6
4
6
8
12
12
18
16
24
20
30
12 is the LCM
Example questions
Examples - 1
15 - 8
7
24
24
1
5 1
8 3
2
2 1
8 - 5
5 4
20
3
1
3
4 12
9 - 1
12
3
20
8 2
12 3
Example questions
Examples - 2
-6
5
3
5
11
4
8
4 8
8
+
14
19
-33
11
7
5
36
36
12 18
6
40 - 27 13
72
72
0
