Three of the following number pairs are alike in some manner and hence form a group. Which number pair does NOT belong to that group? (NOTE : Operations should be performed on the whole numbers, without breaking down the number into its constituent digits. E.g. 13 – Operations on 13 such as adding / subtracting / multiplying etc. to 13 can be performed. Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 is not allowed.)