diff --git a/src/isPrime.js b/src/isPrime.js
new file mode 100644
index 0000000..21cac35
--- /dev/null
+++ b/src/isPrime.js
@@ -0,0 +1,8 @@
+export const isPrime = (num) => {
+    for(let i=1; i<=num/2; i++) {
+        if(num % i == 0){
+            return false;
+        }
+    }
+    return true;
+}
\ No newline at end of file
diff --git a/src/sumOfPrimes.js b/src/sumOfPrimes.js
new file mode 100644
index 0000000..e69de29