In a certain code language, '526' means 'sky is blue' ; '24' means 'blue colour' and '436' means 'colour is fun'. Which digit in that language means 'fun' ?
In the first and third statements, the common code digit is '6' and the common word is 'is'.
So, '6' means 'is'.
In the second and third statements, the common code digit is '4' and the common word is 'colour'.
So, '4' means 'colour'.
Thus, in the statement, '3' means 'fun'.