If the HCF of two number is 23 and the LCM is 4186, one of the two numbers is one of the following: 

a) 276 b) 300 c) 322 d) 345. Which one is it?

Ans. c) 322 

 Both number should be divisible by its HCF and LCM should be divisible by  both the numbers whose  HCF and LCM are to determine. 
 a) 276%23=0
      4186%276=46

b)300%23=1
  4186%300=286

c)322%23=0
 4186%322=0

d)345%23=0
 4186%345=46