diff --git a/tutorials/mesh/blockMesh/sphere/system/blockMeshDict b/tutorials/mesh/blockMesh/sphere/system/blockMeshDict
index 7ef711d3bde6619ff85c17f6b46e035e5bce67c9..a6338486f1cc7e6091b54f2a3bb0d702df72c32f 100644
--- a/tutorials/mesh/blockMesh/sphere/system/blockMeshDict
+++ b/tutorials/mesh/blockMesh/sphere/system/blockMeshDict
@@ -35,7 +35,7 @@ geometry
 }
 
 // Box size
-vo   #eval{ sqrt($outerRadius/3) };
+vo   #eval{ $outerRadius/sqrt(3) };
 
 vertices
 (
diff --git a/tutorials/mesh/blockMesh/sphere7/system/blockMeshDict b/tutorials/mesh/blockMesh/sphere7/system/blockMeshDict
index 6253f9524d35a685f87fbcca7d8c3ad08af0a626..66b82df1e9169c31b61ce88597642932dfc87f36 100644
--- a/tutorials/mesh/blockMesh/sphere7/system/blockMeshDict
+++ b/tutorials/mesh/blockMesh/sphere7/system/blockMeshDict
@@ -38,7 +38,7 @@ geometry
 }
 
 // Outer box size
-vo   #eval{ sqrt($outerRadius/3) };
+vo   #eval{ $outerRadius/sqrt(3) };
 
 // Inner box size - % of overall dimension
 vi   #eval{ $vo * $innerRatio };
diff --git a/tutorials/mesh/blockMesh/sphere7ProjectedEdges/system/blockMeshDict b/tutorials/mesh/blockMesh/sphere7ProjectedEdges/system/blockMeshDict
index 134c50971292b95e58057c0af788a36f491652ed..8e67d39471b33fec5f183c1a44bd4d40c7bf5624 100644
--- a/tutorials/mesh/blockMesh/sphere7ProjectedEdges/system/blockMeshDict
+++ b/tutorials/mesh/blockMesh/sphere7ProjectedEdges/system/blockMeshDict
@@ -45,7 +45,7 @@ geometry
 
 
 // Outer box size (approximate)
-vo   #eval{ sqrt($outerRadius/3) };
+vo   #eval{ $outerRadius/sqrt(3) };
 
 // Inner box size - % of overall dimension
 vi   #eval{ $vo * $innerRatio };