diff --git a/domain-model.md b/domain-model.md
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+++ b/domain-model.md
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+
+| Methods                              | Members | Scenario               | Result                                       |
+|--------------------------------------|---------|------------------------|----------------------------------------------|
+| `calculate(List<Integer> itemCosts)` |         | No item prices in list | total = 0                                    |
+|                                      |         | n items prices in list | total = sum of n item prices                 |
+| `addItem(List<Integer> itemCosts, int newItemCost)`                            |         | Valid itemCost         | Item price gets added at the end of the list |
+|                                      |         | Invalid itemCost       | Item doesn't get added + error message       |
+
+
+
+
+
+
+
+| Methods                                         | Members                      | Scenario                                                                     | Result                              |
+|-------------------------------------------------|------------------------------|------------------------------------------------------------------------------|-------------------------------------|
+| `getNameAndPrice(HashMap<String, Integer> map)` | Hashmap<String, Integer> map | Valid key-value pairs                                                        | return the name and price correctly |
+|                                                 | int quantity                 | Missing keys or value                                                        | return error                        |
+| `getQuantity()`                                 |                              | Valid quantity (not -1)                                                      | return quantity                     |
+|                                                 |                              | Invalid quantity                                                             | return error                        |
+| `calculateTotal(String itemName, int quantity)` |                              | itemName exists in the hashmap as a key and a valid value, quantity is valid | return the total price              |
+|                                                 |                              | Missing or invalid paramets                                                  | return error                        |
+
+
+
+
+
+
diff --git a/src/main/java/com/booleanuk/core/Basket.java b/src/main/java/com/booleanuk/core/Basket.java
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+++ b/src/main/java/com/booleanuk/core/Basket.java
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+package com.booleanuk.core;
+
+import java.util.HashMap;
+
+public class Basket {
+
+    HashMap<String, Integer> items = new HashMap<>();
+    int total = 0;
+
+    public boolean add(String product, int price) {
+        if (!items.containsKey(product)) {
+            items.put(product, price);
+            return true;
+        }
+        return false;
+    }
+
+    public int total() {
+        for (String key : items.keySet()) {
+            total += items.get(key);
+        }
+        return this.total;
+    }
+}
diff --git a/src/test/java/com/booleanuk/core/BasketTest.java b/src/test/java/com/booleanuk/core/BasketTest.java
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index 0000000..1b821aa
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+++ b/src/test/java/com/booleanuk/core/BasketTest.java
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+package com.booleanuk.core;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+public class BasketTest {
+
+    @Test
+    public void itemIsNotAlreadyInBasket() {
+        Basket basket = new Basket();
+        basket.items.put("Apple", 1);
+        basket.items.put("Banana", 20);
+        Assertions.assertTrue(basket.add("TestItem1", 1));
+    }
+
+    @Test
+    public void itemIsAlreadyInBasket() {
+        Basket basket = new Basket();
+        basket.items.put("Apple", 1);
+        basket.items.put("Banana", 20);
+        basket.items.put("TestItem2", 1);
+        Assertions.assertFalse(basket.add("TestItem2", 1));
+    }
+
+    @Test
+    public void totalShouldBeZero() {
+        Basket basket = new Basket() {};
+        Assertions.assertEquals(0, basket.total());
+    }
+
+    @Test
+    public void totalShouldIncrease() {
+        Basket basket = new Basket() {};
+        basket.add("Banana", 20);
+        Assertions.assertEquals(20, basket.total());
+    }
+
+}