diff --git a/09-mostRepeatedChar/index.js b/09-mostRepeatedChar/index.js
index b113ed8..9833767 100644
--- a/09-mostRepeatedChar/index.js
+++ b/09-mostRepeatedChar/index.js
@@ -1,4 +1,34 @@
-export function mostUsedChar(text) {
-    // implementar logica aqui
-    return ""
-}
\ No newline at end of file
+export function mostUsedChar(str) {
+    const charMap = {};
+    let max = 0;
+    let mostUsedChar = '';
+  
+    // create character map
+    for (let char of str) {
+      if (charMap[char]) {
+        // increment the character's value if the character existed in the map
+        charMap[char]++;
+      } else {
+        // Otherwise, the value of the character will be increamented by 1
+        charMap[char] = 1;
+      }
+    }
+  
+    // find the most commonly used character
+    for (let char in charMap) {
+      if (charMap[char] > max) {
+        max = charMap[char];
+        mostUsedChar = char;
+      }
+    }
+  
+    return mostUsedChar;
+  }
+
+  console.log(mostUsedChar("fdgdfgff"));
+  
+  console.log(mostUsedChar("Lorem ipsum"));
+  
+  console.log(mostUsedChar("adsassdasd"));
+  
+  console.log(mostUsedChar("testeeeee"));
\ No newline at end of file