Going by the mechanism of hydrolysis under basic medium, the lone pair of water will attack on C=O carbon.  

Due to the negative mesomeric (-M/-R) effect and negative inductive effect of the nitro group, the C=O will act as a more electrophilic substrate as compared to the one which is has ether substituent,  

(which due to its +M and +I effect will reduce the electrophilic character of the C=O ),  
will be easier to hydrolyse.  

The effect of solvation on substituents is less likely to tell which compound will hydrolyse easily as it is not the [Rate Determining Step](//www.google.com/search?q=rate+determining+step+of+nucleophilic+addition+elimination&oq=rate+determining+&aqs=chrome.1.69i57j35i39j0l2.6387j0j7&client=ms-android-oneplus&sourceid=chrome-mobile&ie=UTF-8) of the reaction. So although the observation is not wrong, its still not the deciding factor.