Question

The LCM and HCF of two rational numbers are equal,then the numbers must be --------- a)prime b)co-prime c)composite d)equal

Answer 1

The LCM and HCF of two rational numbers are equal,then the numbers must be EQUAL.

Answer 2

The LCM and HCF of two rational numbers are equal, then the numbers must be d) equal.

For example, taking a number 10,  

HCF of 10 and 10 = 10,  

LCM of 10 and 10 = 10.

LCM and HCF are considered to be rational numbers and hence they are equal, if considering the prime numbers for HCF and LCM prime numbers will not be equal to their HCF or LCM, in cases of co-primes the value of HCF will always be 1 and hence that will not be a possible answer.

Coming to the option composite are the numbers that are not a prime numbers hence this is not the correct answer.