diff --git a/src/system.ts b/src/system.ts
index 063941f0159..33413a23bc6 100644
--- a/src/system.ts
+++ b/src/system.ts
@@ -76,24 +76,6 @@ export class System {
    * faker.system.mimeType() // 'video/vnd.vivo'
    */
   mimeType(): string {
-    const typeSet = new Set<string>();
-    const extensionSet = new Set();
-    const mimeTypes = this.faker.definitions.system.mimeTypes;
-
-    Object.keys(mimeTypes).forEach((m) => {
-      const type = m.split('/')[0];
-
-      typeSet.add(type);
-
-      if (mimeTypes[m].extensions instanceof Array) {
-        mimeTypes[m].extensions.forEach((ext) => {
-          extensionSet.add(ext);
-        });
-      }
-    });
-
-    const types = setToArray(typeSet);
-    const extensions = setToArray(extensionSet);
     const mimeTypeKeys = Object.keys(this.faker.definitions.system.mimeTypes);
 
     return this.faker.random.arrayElement(mimeTypeKeys);
@@ -129,24 +111,15 @@ export class System {
    */
   fileType(): string {
     const typeSet = new Set<string>();
-    const extensionSet = new Set();
     const mimeTypes = this.faker.definitions.system.mimeTypes;
 
     Object.keys(mimeTypes).forEach((m) => {
       const type = m.split('/')[0];
 
       typeSet.add(type);
-
-      if (mimeTypes[m].extensions instanceof Array) {
-        mimeTypes[m].extensions.forEach((ext) => {
-          extensionSet.add(ext);
-        });
-      }
     });
 
     const types = setToArray(typeSet);
-    const extensions = setToArray(extensionSet);
-    const mimeTypeKeys = Object.keys(this.faker.definitions.system.mimeTypes);
     return this.faker.random.arrayElement(types);
   }
 
@@ -160,15 +133,15 @@ export class System {
    * faker.system.fileExt('application/json') // 'json'
    */
   fileExt(mimeType?: string): string {
-    const typeSet = new Set<string>();
-    const extensionSet = new Set<string>();
+    if (typeof mimeType === 'string') {
+      const mimes = this.faker.definitions.system.mimeTypes;
+      return this.faker.random.arrayElement(mimes[mimeType].extensions);
+    }
+
     const mimeTypes = this.faker.definitions.system.mimeTypes;
+    const extensionSet = new Set<string>();
 
     Object.keys(mimeTypes).forEach((m) => {
-      const type = m.split('/')[0];
-
-      typeSet.add(type);
-
       if (mimeTypes[m].extensions instanceof Array) {
         mimeTypes[m].extensions.forEach((ext) => {
           extensionSet.add(ext);
@@ -176,14 +149,7 @@ export class System {
       }
     });
 
-    const types = setToArray(typeSet);
     const extensions = setToArray(extensionSet);
-    const mimeTypeKeys = Object.keys(this.faker.definitions.system.mimeTypes);
-
-    if (mimeType) {
-      const mimes = this.faker.definitions.system.mimeTypes;
-      return this.faker.random.arrayElement(mimes[mimeType].extensions);
-    }
 
     return this.faker.random.arrayElement(extensions);
   }