diff --git a/src/chain-of-responsability/Readme.md b/src/chain-of-responsability/Readme.md
new file mode 100644
index 0000000..e69de29
diff --git a/src/chain-of-responsability/discounts-calculator/Budget.ts b/src/chain-of-responsability/discounts-calculator/Budget.ts
index 6ac23ca..18c478b 100644
--- a/src/chain-of-responsability/discounts-calculator/Budget.ts
+++ b/src/chain-of-responsability/discounts-calculator/Budget.ts
@@ -17,4 +17,14 @@ export default class Budget {
 
     return nItems;
   }
+
+  getTotal(): number {
+    return this.items
+      .map((product: Product) => {
+        return product.price;
+      })
+      .reduce((prev: number, current: number) => {
+        return prev + current;
+      }, 0);
+  }
 }
diff --git a/src/chain-of-responsability/discounts-calculator/Calculator.ts b/src/chain-of-responsability/discounts-calculator/Calculator.ts
new file mode 100644
index 0000000..0cc016c
--- /dev/null
+++ b/src/chain-of-responsability/discounts-calculator/Calculator.ts
@@ -0,0 +1,20 @@
+import Budget from "./Budget";
+
+export default class Calculator {
+  constructor(private budged: Budget) {}
+
+  calculate(): number {
+    const total: number = this.budged.getTotal();
+    let discount = 0;
+    // discount more than 2 items
+    if (this.budged.getItems().length > 2) {
+      discount += total * 0.1;
+    }
+
+    if (total > 500) {
+      discount += total * 0.07;
+    }
+
+    return total - discount;
+  }
+}
diff --git a/src/chain-of-responsability/discounts-calculator/index.ts b/src/chain-of-responsability/discounts-calculator/index.ts
index a505f27..e673dd9 100644
--- a/src/chain-of-responsability/discounts-calculator/index.ts
+++ b/src/chain-of-responsability/discounts-calculator/index.ts
@@ -1,4 +1,5 @@
 import Budged from "./Budget";
+import Calculator from "./Calculator";
 
 const budget = new Budged();
 
@@ -7,4 +8,6 @@ budget
   .add({ code: "B335", name: "Monitor LG Ultrawide 29", price: 1500.0 })
   .add({ code: "V887", name: "Suporte Monitor Top", price: 300.0 });
 
-  
\ No newline at end of file
+const calculator = new Calculator(budget);
+
+console.log(calculator.calculate())
\ No newline at end of file