Your calculation is based on some misconceptions:
- ram is no storage. It's the memory used to run active apps (see our ram tag-wiki for details)
- ROM is a misleading term here (and in many other places). What's actually meant in this context ist storage. So these 4 GB is what you're looking for.
Now, storage on Android devices is devided into multiple partitions. Typical partitions are
/data for the user data, and the read-only
/system partition for the actual OS files. The latter is usually not included in "storage summaries". I don't know your device, but from the data given can assume:
- 1 GB "internal SD-Card"
- 1.42 GB "internal storage (
- remaining storage devided into:
/system: probably about 1 GB
/boot: files for system start
/recovery: for the recovery-menu
- and maybe some more small partitions
So there's nothing wrong; specifications have just not been given in a way clearly understandable by the end-user.
Recommendations for further reading:
And always: Check the links in the "linked" and "related" section of questions, they might (and in most times do) lead to more useful information. Same for the "related" section, and the tags and links (just hover your mouse over a tag to reveal additional information/links).