I bought an Android 4.1.1 tablet, the ad said "comes with 8 GB". But when I go to the system configuration I get:

INTERNAL
1,18 GB total
Apps 0,90 GB
Available 161 MB

NAND FLASH
Total 4,55 GB
Free 4,17 GB

I ask the vendor where is the 8 GB, and they said: "the tablet comes with physical 8GB, but the Android System makes a partition for different purposes (Recovery, Loader, Apps, etc.) letting available for the user only 4 GB. The others partitions are not visible for the user. This is the same for all Android devices".

They are telling me the truth? or just are a bunch of liars and sold me an 4GB tablet ?

Android 4.1.1
Core 3.0.8+
Compilation P758.6.01.01.20
Brand: NOBLEX - Model: T7014AR
(official specification: RAM 1GB - Internal 8GB)
http://www.noblex.com.ar/tablets/T7014AR

Thanks a lot.

EDIT:

u0_a78@android:/ $ df
Filesystem             Size   Used   Free   Blksize
/dev                  443.2M  36.0K  443.2M   4096
/mnt/asec             443.2M  0.0 K  443.2M   4096
/mnt/obb              443.2M  0.0 K  443.2M   4096
/system               607.4M  440.2M  167.2M  1024
/data                 1.2 G   1.0 G  153.8M   4096
/cache                629.9M  16.5M  613.4M   4096
/mnt/external_sd      941.7M  16.0K  941.7M   16384
/mnt/sdcard           4.5 G   382.1M  4.2 G   8192
/mnt/secure/asec: Permission denied
/mnt/asec/com.robotinvader.fooding-1  36.5M  34.8M  1.7 M   4096
/mnt/asec/com.vkcode.SpaceTube-1  14.2M  12.6M  1.6 M   4096
1|u0_a78@android:/ $