Question 1 How do you find the Least Common Multiple (LCM) of 28, 14, and 21? Answer 1 To find the LCM of 28, 14, and 21: List the multiples of each number until you find the first common multiple: Multiples of 28: 28, 56, 84, ... Multiples of 14: 14, 28, 42, 56, 70, 84, ... Multiples of 21: 21, 42, 63, 84, ... The smallest common multiple is 84. LCM(28, 14, 21) = 84 Alternate method: Prime factorization: 28 = 2 2 × 7 , 14 = 2 × 7 , 21 = 3 × 7 28=2 2 ×7,14=2×7,21=3×7 Take the highest powers of each prime factor: 𝐿 𝐶 𝑀 = 2 2 × 3 × 7 = 84 LCM=2 2 ×3×7=84 Result: 84 Question 2 Is 25 a composite number? Answer 1 Yes, 25 is a composite number because it has factors other than 1 and itself (1, 5, and 25). Question 3 What's the Lowest Common Multiple (LCM) of 12 and 15? Answer 1 The LCM of 12 and 15 can be found by prime factorization: 12 = 2 2 × 3 12=2 2 ×3 15 = 3 × 5 15=3×5 Take the highest powers of each prime factor: 𝐿 𝐶 𝑀 = 2 2 × 3 × 5 = 4 × 3 × 5 = 60 LCM=2 2 ×3×5=4×3×5=60 Result: 60 Question 4 What is 2 × 3 × 5 × 5 2×3×5×5? Answer 1 Calculate the product: 2 × 3 × 5 × 5 = 6 × 25 = 150 2×3×5×5=6×25=150 Therefore, 150 = 2 \times 3 \times 5 \times 5. Question 5 Is 37 composite or prime? Answer 1 37 is a prime number because it has no factors other than 1 and itself.