- A3
- B4
- C2
- D6
Step-by-Step Solution
Write them as and with a, co-prime and : (1, 8), (2, 7), (4, 5). (3, 6) is excluded since 3 and 6 are not co-prime. So 3 pairs.
Answer: A) 3
Two natural numbers have HCF 7 and add up to 63. How many such pairs are there (order not counted)?
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