diff --git a/extra/math/ratios/ratios.factor b/extra/math/ratios/ratios.factor
index b71a34022a..6569ee9540 100755
--- a/extra/math/ratios/ratios.factor
+++ b/extra/math/ratios/ratios.factor
@@ -51,5 +51,5 @@ M: ratio * 2>fraction * >r * r> / ;
 M: ratio / scale / ;
 M: ratio /i scale /i ;
 M: ratio /f scale /f ;
-M: ratio mod 2dup >r >r /i r> r> rot * - ;
+M: ratio mod [ /i ] 2keep rot * - ;
 M: ratio /mod [ /i ] 2keep mod ;