Question

if the HCF and LCM of two number are 6 and 210 respectively and one of the number is 42 find the other number

Answer 1

let no. are a , b
LCM * HCF = a*b
6*210 = 42*b
b = 210*6/42
b = 5*6
b = 30

Answer 2

HCF IS.......=6
LCM IS........=210
one no. of them =42

then second no. = LCM ×HCF /FIRST NO.
1260/42 = 30 ans