Increase value of all numbers by fixed amount?

Hey, I have a document with a lot of decimal numbers all of which I want to increase by a certain, fixed amount. E.g.:
<top y="333.6278728890073" x="1451.050664666312"/> <bottom y="4390.939329772518" x="1464.328232757782"/> <left y="2365.94191802627" x="339.7942031872444"/> <right y="2358.625284635257" x="2575.584694236849"/>
Increased by, say, 5 to:
<top y="338.6278728890073" x="1456.050664666312"/> <bottom y="4395.939329772518" x="1469.328232757782"/> <left y="2370.94191802627" x="344.7942031872444"/> <right y="2363.625284635257" x="2580.584694236849"/>
Does anyone know how to go about this? Would it be possible using the Find and Replace function? Thanks for any help!
