Q. The product of two numbers is 2160 and their HCF is 12. Number of such possible pairs is :
Answer: 2
Notes: HCF = 12
Numbers = 12x and 12y
where x and y are prime to each other
$latex \therefore 12x \times 12y = 2160$
$latex => xy = \frac{2160}{12\times 12} = 15&s=1$
$latex \because 15 = 3\times 5,\ 1\times 15$
Possible pairs = (36, 60) and (12, 80)
Hence option [B] is correct answer.