Samsung Galaxy Tab 7.7 has a pixel density of:
196.03

A.K.A. Tab 7.7
Released: 2011

Resolution: 1280×800 7.7″ display

Wide XGA (WXGA) 1280×800, 8:5 aspect ratio

Totaling 1.02mp (megapixels) and having a PPI of 196.03

Category: Tablet
Tags: galaxy tab, android, tablet

Samsung Galaxy Tab 7.7

Developer	Samsung
First released	February 2012
Predecessor	Samsung Galaxy Tab
Related	Samsung Galaxy S II Samsung Galaxy Note series Samsung Galaxy Tab 7.0 Plus Samsung Galaxy Tab 2 7.0 Samsung Galaxy Tab 3 7.0
Type	Tablet, media player, PC
Dimensions	196.7 mm (7.74 in) H 133.0 mm (5.24 in) W 7.9 mm (0.31 in) D
Mass	340 g (0.75 lb)
Operating system	Android 3.2 Honeycomb upgradable to Android 4.1 Jelly Bean
CPU	1.4 GHz dual-core ARM Cortex-A9 SoC processor Samsung Exynos 4210
GPU	ARM Mali-400 MP[1][2]
Memory	1 GB
Storage	16/32/64 GB flash memory, microSD slot (up to 32 GB)
Data inputs	Multi-touch screen, headset controls, proximity and ambient light sensors, 3-axis gyroscope, magnetometer, accelerometer, aGPS, USB (adapter needed)
Display	1280×800 px (1 megapixel), 7.7 in (20 cm) diagonal, 197 ppi, Super AMOLED Plus display
Rear camera	3.0 MP AF camera with LED flash, 2.0 MP front facing (for video calls)
Connectivity	HSPA+ 21 Mbit/s 850/900/1900/2100 MHz EDGE/GPRS 850/900/1800/1900 MHz Wi-Fi 802.11a/b/g/n, Bluetooth 3.0, HDMI (external cable)
Website	www.samsung.com/global/microsite/galaxytab/7.7

This righthand infobox courtesy of Wikipedia.