What is the HCF of 0.63 and 1.05?
2023
What is the HCF of 0.63 and 1.05?
Answer: B. 0.21 — Answer: 0.21 Explanation Step 1: Remove decimals by multiplying both numbers by 100: 0.63 → 63 and 1.05 → 105. Step 2: Find the HCF (GCD) of 63 and 105. Use…
- A.
0.98
- B.
0.21
- C.
0.20
- D.
0.89
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Show answer & explanation
Correct answer: B
Answer: 0.21
Explanation
Step 1: Remove decimals by multiplying both numbers by 100: 0.63 → 63 and 1.05 → 105.
Step 2: Find the HCF (GCD) of 63 and 105. Use prime factors: 63 = 3² × 7, 105 = 3 × 5 × 7. The common factors are 3 and 7, so the GCD = 3 × 7 = 21.
Step 3: Convert back to decimals by dividing the GCD by 100: 21 ÷ 100 = 0.21. Therefore the HCF of 0.63 and 1.05 is 0.21.
Quick check: 0.63 ÷ 0.21 = 3 and 1.05 ÷ 0.21 = 5, both integers, confirming 0.21 is the greatest common factor.