diff --git a/searches/binary_search.py b/searches/binary_search.py
index 0966cd8de..88fee4715 100644
--- a/searches/binary_search.py
+++ b/searches/binary_search.py
@@ -51,7 +51,7 @@ def bisect_left(
         hi = len(sorted_collection)
 
     while lo < hi:
-        mid = (lo + hi) // 2
+        mid = lo + (hi - lo) // 2
         if sorted_collection[mid] < item:
             lo = mid + 1
         else:
@@ -96,7 +96,7 @@ def bisect_right(
         hi = len(sorted_collection)
 
     while lo < hi:
-        mid = (lo + hi) // 2
+        mid = lo + (hi - lo) // 2
         if sorted_collection[mid] <= item:
             lo = mid + 1
         else: