Update README.md

Author: SergeStinckwich

README.md

@@ -20,7 +20,7 @@
 <img width="1675" alt="Screenshot 2019-04-24 at 11 12 57" src="https://user-images.githubusercontent.com/327334/56652094-66eb7780-6682-11e9-9753-101be18df67c.png">
 
 
-You can load PolyMath 1.0.3 into a fresh Pharo 8.0 image with:
+You can load PolyMath 1.0.3 into a fresh Pharo 9.0 image with:
 
 ```Smalltalk
 Metacello new