Question

25. The HCF of two numbers is 21 and their sum is
105. The LCM of the numbers is
(a) 189 or 147
b) 126 or 84
(c) 84 or 145
(d) 126 of 145​

Answer 1

Let x & y be two numbers

HCF(x,y) = 21

x = 21a

y = 21b

21a + 21b = 105

a + b = 5, a and b are co-primes

a=1 b= 4

Numbers = 21,84

LCM = 84

Option C