diff --git a/src/main/java/study2/Calculator.java b/src/main/java/study2/Calculator.java
new file mode 100644
index 000000000..6ce5dd037
--- /dev/null
+++ b/src/main/java/study2/Calculator.java
@@ -0,0 +1,21 @@
+package study2;
+
+public class Calculator {
+
+    public int add(int a, int b) {
+        return a + b;
+    }
+
+    public int subtraction(int a, int b) {
+        return a - b;
+    }
+
+    public int multiplication(int a, int b) {
+        return a * b;
+    }
+
+    public int division(int a, int b) {
+        return a / b;
+    }
+
+}
diff --git a/src/test/java/study/CalculatorMain.java b/src/test/java/study/CalculatorMain.java
new file mode 100644
index 000000000..e4a71a953
--- /dev/null
+++ b/src/test/java/study/CalculatorMain.java
@@ -0,0 +1,15 @@
+package study;
+
+import study2.Calculator;
+
+public class CalculatorMain {
+
+    public static void main(String[] args) {
+        Calculator cal = new Calculator();
+        cal.add(3,4);
+        cal.subtraction(5,2);
+        cal.multiplication(4,6);
+        cal.division(8,4);
+    }
+
+}
diff --git a/src/test/java/study/CalculatorMainTest.java b/src/test/java/study/CalculatorMainTest.java
new file mode 100644
index 000000000..bfc9fb903
--- /dev/null
+++ b/src/test/java/study/CalculatorMainTest.java
@@ -0,0 +1,32 @@
+package study;
+
+import org.junit.jupiter.api.Test;
+import study2.Calculator;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class CalculatorMainTest {
+
+    Calculator calc = new Calculator();
+
+    @Test
+    void testAdd() {
+        assertEquals(5, calc.add(2,3));
+    }
+
+    @Test
+    void testSubtraction() {
+        assertEquals(1, calc.subtraction(3,2));
+    }
+
+    @Test
+    void testMultiplication() {
+        assertEquals(6, calc.multiplication(2,3));
+    }
+
+    @Test
+    void testDivision() {
+        assertEquals(2, calc.division(6,3));
+    }
+
+}
\ No newline at end of file