Default [Q] Huawei Ascend Y200 how to delete .apk

Hello, I have ascend y200 and I have memory issue, I can't install new applications because i have 4 mb free. So the logical solution would be to uninstall other applications right? NO, I have only 3 applications installed - google play, air droid and viber.
Searching the phone, I found many non installed APK, which are stored in "appinstall" I believe that they take up the most of the memory.
The problem is, there is no option do delete them, If I click on them I get only install option, nothing else. On airdroid I can't find any of those APK, how can I delete that?