First you want to turn both into either a fraction or decimal.
% would be easier for this one.
Adding a 0 after a decimal doesn't change the value of the number so we'll add a 0 to the .9 to make it .90
.90= 90%
88%< 90%
88%< .9
If you want to make both a decimals just turn the 88% into .88
.88< .9
