LCM of two numbers is 28 times their HCF. The sum of HCF and LCM is 1740. If one of these numbers is 240, the sum of digits of the other number is -
A) 2
B) 5
C) 6
D) 8
LCM = 28 HCF
HCF + LCM = 1740
HCF + 28HCF = 1740
29HCF = 1740
HCF = 60
LCM = 1680
HCF * LCM = Product of numbers
60 * 1680 = 240 * x
x = 60 * 1680 / 240
x = 1680 / 4 = 420
Sum of digits = 4 + 2 + 0 = 6
Ans: C) 6