Viacom's worth has declined in the past year due to the whole ordeal with Philippe Dauman, Sumner Redstone's legacy (voting shares, trust, Shari, etc.), ratings woes and Dish renewal. Their assets are highly valuable but the sideshow listed above has made Viacom share price, and consequently worth, cut in half.
Paramount is easily worth north of $5B+ (LionsGate was previously worth $5B at the height of Katniss' reign).
Paramount's slate was terrible in 2015, is mediocre for 2016. 2017 is solid as fuck with upcoming hits like Mission Impossible 6, WWZ2 & Transformers - that's what they are banking on. There's value in Paramount, but that won't be unlocked until 2017 hits, and China wants in.