Answer:
A.
1. A. 15, 40 = 5
15 = 3 x 5
40 = 5 x 7
B. 21, 49 = 7
21 = 3 x 7
49 = 2 x 2 x 7
C. 24, 32 = 8
24 = 2 x 2 x 2 x 3
32 = 2 x 2 x 2 x 4
GCF: 2 x 2 x 2 = 8
2. A. 16, 20 = 80
LCM: 2 x 2 x 2 x 2 x 5
B. 32, 36 = 288
LCM: 2 x 2 x 2 x 2 x 2 x 3 x 3
C. 35, 42 = 210
LCM: 2 x 3 x 5 x 7
B.
1. 18, 20
GCF: 2
LCM: 180
Solution:
GCF: 18 = 2 x 3 x 3
20 = 2 x 2 x 5
LCM: 2 x 2 x 3 x 3 x 5
2. 24, 40
GCF = 8
LCM = 120
Solution:
GCF: 24 = 2 x 2 x 2 x 3
40 = 2 x 2 x 2 x 5
LCM: 2 x 2 x 2 x 3 x 5
3. 27, 45
GCF: 9
LCM: 135
Solution:
GCF: 27 = 3 x 3 x 3
45 = 3 x 3 x 5
LCM: 3 x 3 x 3 x 5
4. 36, 48
GCF: 12
LCM: 144
Solution:
GCF: 36 = 2 x 2 x 3 x 5
48 = 2 x 2 x 2 x 2 x 3
LCM: 2 x 2 x 2 x 2 x 3 x 3
5. 30, 42
GCF: 6
LCM: 210
Solution:
GCF: 30 = 2 x 3 x 5
42: 2 x 3 x 7
LCM: 3 x 3 x 3 x 5
