e HCF for these sets of numbers. \( \begin{array}{ll}\text { and } 84 & \text { b) } 108 \text { and } 270 \\ 210 \text { and } 700 & \text { d) } 195 \text { and } 330\end{array} \)

It looks like you're looking to find the Highest Common Factor (HCF), also known as the Greatest Common Divisor (GCD), for several pairs of numbers. Based on your input, I'll address the following pairs: - **a)** (Missing number) and **84** - **b)** **108** and **270** - **c)** **210** and **700** - **d)** **195** and **330** Since the first pair (**a**) is missing one number, I'll proceed with the calculations for parts **b**, **c**, and **d**. --- ### **b) HCF of 108 and 270** 1. **Prime Factorization**: - 108 = 2² × 3³ - 270 = 2 × 3³ × 5 2. **Common Factors**: - **2¹** (the lowest power of 2 in both) - **3³** (the lowest power of 3 in both) 3. **HCF Calculation**: - HCF = 2¹ × 3³ = 2 × 27 = **54** --- ### **c) HCF of 210 and 700** 1. **Prime Factorization**: - 210 = 2 × 3 × 5 × 7 - 700 = 2² × 5² × 7 2. **Common Factors**: - **2¹** - **5¹** - **7¹** 3. **HCF Calculation**: - HCF = 2¹ × 5¹ × 7¹ = 2 × 5 × 7 = **70** --- ### **d) HCF of 195 and 330** 1. **Prime Factorization**: - 195 = 3 × 5 × 13 - 330 = 2 × 3 × 5 × 11 2. **Common Factors**: - **3¹** - **5¹** 3. **HCF Calculation**: - HCF = 3¹ × 5¹ = 3 × 5 = **15** --- ### **Summary of HCFs:** - **b)** HCF of 108 and 270 is **54** - **c)** HCF of 210 and 700 is **70** - **d)** HCF of 195 and 330 is **15** If you provide the missing number for part **a)**, I'd be happy to help calculate its HCF with 84!