Examining the given reaction:
Li2O + H2O ........> 2LiOH
we find that, 1 mole of Li2O is required to react with one mole of H2O in order to produce two moles of LiOH.
Therefore, the ration between the required Li2O and H2O is 1:1
Based on this, 2.2 moles of H2O (water) are required to react with 2.2 moles of Li2O