diff --git a/beli.js b/beli.js
index 060efcd..036c691 100644
--- a/beli.js
+++ b/beli.js
@@ -1,15 +1,17 @@
-function beli(uang, obj, cb){
-  console.log(`Saya pergi membeli ${obj.item}`)
-  setTimeout(function(){
-    let kembalian = uang - obj.harga
-    if (kembalian > 0) {
-      console.log(`Saya sudah membeli ${obj.item} uang kembaliannya ${kembalian}`);
-      cb(kembalian)
-    }else{
-      console.log(`uang gk cukup nih buat beli ${obj.item} kembaliannya cuma ${kembalian}`);
-      cb(0)
-    }
-  }, obj.waktu);
+function beli(uang, obj){
+  return new Promise (function(resolve, reject){
+    console.log(`Saya pergi membeli ${obj.item}`)
+    setTimeout(function(){
+      let kembalian = uang - obj.harga
+      if (kembalian > 0) {
+        console.log(`Saya sudah membeli ${obj.item} uang kembaliannya ${kembalian}`);
+        resolve(kembalian)
+      }else{
+        console.log(`uang gk cukup nih buat beli ${obj.item} kembaliannya cuma ${kembalian}`);
+        reject(0)
+      }
+    }, obj.waktu);
+  })
 }
 
 module.exports = beli;
diff --git a/index.js b/index.js
index e69de29..401df0d 100644
--- a/index.js
+++ b/index.js
@@ -0,0 +1,62 @@
+const beli = require('./beli.js')
+
+let obj5 = {
+    item: 'kaos',
+    harga: 100000,
+    waktu: 1000
+}
+let obj6= {
+    item: 'sepatu',
+    harga: 350000,
+    waktu: 1000
+}
+let obj7= {
+    item: 'sendal',
+    harga: 80000,
+    waktu: 1000
+}
+let obj8= {
+    item: 'topi',
+    harga: 60000,
+    waktu: 1000
+}
+let obj9= {
+    item: 'jaket',
+    harga: 200000,
+    waktu: 1000
+}
+
+let duit = 1500000
+
+
+beli(duit, obj5)
+    .then(function(kembalian){
+        beli(kembalian, obj6)
+            .then(function(kembalian){
+                beli(kembalian, obj7)
+                    .then(function(kembalian){
+                        beli(kembalian, obj8)
+                            .then(function(kembalian){
+                                beli(kembalian, obj9)
+                                    .then(function(kembalian){
+
+                                    })
+                                    .catch(function(err){
+                                        console.log(err)
+                                    })
+                            })
+                            .catch(function(err){
+                                console.log(err)
+                            })
+                    })
+                    .catch(function(err){
+                        console.log(err)
+                    })
+            })
+            .catch(function(err){
+                console.log(err)
+            })
+    })
+    .catch(function(err){
+        console.log(err)
+    })
\ No newline at end of file