diff --git a/book/src/02_basic_calculator/10_as_casting.md b/book/src/02_basic_calculator/10_as_casting.md
index bbf837c..e878f63 100644
--- a/book/src/02_basic_calculator/10_as_casting.md
+++ b/book/src/02_basic_calculator/10_as_casting.md
@@ -46,7 +46,7 @@ To understand what happens, let's start by looking at how `256u16` is
 represented in memory, as a sequence of bits:
 
 ```text
- 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0
+ 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0
 |               |               |
 +---------------+---------------+
   First 8 bits    Last 8 bits