diff --git a/src/calculator.ts b/src/calculator.ts
new file mode 100644
index 0000000..def5678
--- /dev/null
+++ b/src/calculator.ts
@@ -0,0 +1,36 @@
+export class Calculator {
+  
+  static divide(a: number, b: number): number {
+    if (b === 0) {
+      throw new Error('Division by zero');
+    }
+    return a / b;
+  }
+  
+  static getGrade(score: number): string {
+    if (score >= 90) {
+      return 'A';
+    } else if (score >= 80) {
+      return 'B';
+    } else if (score >= 70) {
+      return 'C';
+    } else if (score >= 60) {
+      return 'D';
+    } else {
+      return 'F';
+    }
+  }
+} 