1. 30
Solution:
- List down the first ten multiples of each denominator.
6 = 6 , 12 , 18 , 24, 30 , 36, 42, 48 , 54, 60
5 = 5, 10 , 15 , 20 , 25 , 30 , 35 , 40 , 45 , 50
- Find a common multiple with the least/lowest value.
6 = 6 , 12 , 18 , 24, 30 , 36, 42, 48 , 54, 60
5 = 5, 10 , 15 , 20 , 25 , 30 , 35 , 40 , 45 , 50
Therefore, the LCD is 30.
2. 20
Solution:
- List down the first ten multiples of each denominator.
10 = 10 , 20 , 30 , 40 , 50 , 60 , 70 , 80 , 90 , 100
4 = 4 , 8 , 12 , 16, 20 , 24 , 28 , 32 , 36 , 40
- Find a common multiple with the least/lowest value.
10 = 10 , 20 , 30 , 40 , 50 , 60 , 70 , 80 , 90 , 100
4 = 4 , 8 , 12 , 16, 20 , 24 , 28 , 32 , 36 , 40
Therefore, the LCD is 20.
3. 40
Solution:
- List down the first ten multiples of each denominator.
20 = 20 , 40 , 60 , 80 , 100 , 120 , 140 , 160 , 180 , 200
8 = 8 , 16, 24 , 32 , 40 , 48 , 56 , 64, 72 , 80
- Find a common multiple with the least/lowest value.
20 = 20 , 40 , 60 , 80 , 100 , 120 , 140 , 160 , 180 , 200
8 = 8 , 16, 24 , 32 , 40 , 48 , 56 , 64, 72 , 80
Therefore, the LCD is 40.
4. 10
Solution:
- List down the first ten multiples of each denominator.
5 = 5 , 10 , 15 , 20 , 25 , 30 , 35 , 40 , 45 , 50
2 = 2 , 4 , 6 , 8 , 10 , 12 , 14 , 16 , 18 , 20
- Find a common multiple with the least/lowest value.
5 = 5 , 10 , 15 , 20 , 25 , 30 , 35 , 40 , 45 , 50
2 = 2 , 4 , 6 , 8 , 10 , 12 , 14 , 16 , 18 , 20
Therefore, the LCD is 10.
5. 20
Solution:
- List down the first ten multiples of each denominator.
4 = 4 , 8 , 12 , 16, 20 , 24 , 28 , 32 , 36 , 40
10 = 10 , 20 , 30 , 40 , 50 , 60 , 70 , 80 , 90 , 100
- Find a common multiple with the least/lowest value.
4 = 4 , 8 , 12 , 16, 20 , 24 , 28 , 32 , 36 , 40
10 = 10 , 20 , 30 , 40 , 50 , 60 , 70 , 80 , 90 , 100
Therefore, the LCD is 20.
