diff --git a/IV/mj-msc.tex b/IV/mj-msc.tex
index 3c8732d..839df8e 100644
--- a/IV/mj-msc.tex
+++ b/IV/mj-msc.tex
@@ -592,7 +592,7 @@ half-circle's diameter and adjusted size. These easily derive from circle's
 area formula $A = 2\pi r^2$. Diameter:
 
 \[
-  D = 2\sqrt{2 adjsize / \pi}
+    D = 2\sqrt{\frac{2 adjsize}{\pi}}
 \]
 
 In reverse, half-circle's area from it's diameter (adjusted size):