The sum of two numbers is 135 and their HCF is 9. How many such pairs of numbers can be formed ?
Let the two numbers be $$9x$$ and $$9y$$, where $$x$$ and $$y$$ are co prime numbers.
Now, pairs of natural numbers having sum 15 and co prime are = (1,14), (2,13), (4,11), (7,8)
Thus, 4 such pairs can be formed.
=> Ans - (C)
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