diff --git a/lib/bowling_game.dart b/lib/bowling_game.dart
index e58e92b..2cc3615 100644
--- a/lib/bowling_game.dart
+++ b/lib/bowling_game.dart
@@ -10,7 +10,7 @@ class BowlingGame {
     int rollIndex = 0;
 
     for (int frame = 0; frame < 10; frame++) {
-      if (_rolls[rollIndex] + _rolls[rollIndex + 1] == 10) {
+      if (_isSpare(rollIndex)) {
         totalScore += 10 + _rolls[rollIndex + 2];
         rollIndex += 2;
       } else {
@@ -21,4 +21,8 @@ class BowlingGame {
 
     return totalScore;
   }
+
+  bool _isSpare(int rollIndex) {
+    return _rolls[rollIndex] + _rolls[rollIndex + 1] == 10;
+  }
 }