diff --git a/exercises/02_basic_calculator/09_saturating/src/lib.rs b/exercises/02_basic_calculator/09_saturating/src/lib.rs
index 4b0adde..a254b43 100644
--- a/exercises/02_basic_calculator/09_saturating/src/lib.rs
+++ b/exercises/02_basic_calculator/09_saturating/src/lib.rs
@@ -1,9 +1,9 @@
 pub fn factorial(n: u32) -> u32 {
-    let mut result = 1;
+    let mut result: u32 = 1;
     for i in 1..=n {
         // Use saturating multiplication to stop at the maximum value of u32
         // rather than overflowing and wrapping around
-        result *= i;
+        result = result.saturating_mul(i);
     }
     result
 }