After a 25% decrease, the remaining water is 75% of the original amount.<br><br>&bull; 75% &rarr; 90 ml<br>&bull; 1% &rarr; 90 &divide; 75 = 1.2 ml<br>&bull; 100% &rarr; 1.2 &times; 100 = 120 ml<br><br>Final Answer: 120 ml