In a certain code language, '743' means 'mangoes are good' ; '657' means 'eat good food' and '934' means 'mangoes are ripe'. Which digit means 'ripe' in that language ?
In the first and third statements, the common code digits are '4' and '3' and the common words are 'mangoes' and 'are'.
So, '4' and '3' are the codes for 'mangoes' and 'are'.
Thus, in the third statements, '9' means 'ripe'.