Depends on where you are. Not much. Average income in Moscow is (probably) about $300 a month. Professors earn less, because they are state employees, and the state is broke.
The exchange rate is about 31 rubles to the dollar. Let's see: A loaf of bread is about 5 rubles, a pack of disgusting filterless Prima cigarettes is 3 rubles (Marlboros are about 25), the Moscow metro costs 7 rubles, sausage about 80 rubles per kilo, instant Korean doshirak soup (which is what poor people eat) 15 rubles, a pair of jeans about 700 rubles, a carton of j-7 juice about 30 rubles. So, not much, but you can survive on it. I wouldn't like trying it, however. Good luck raising a family on it.
Of course, that many people own their own apartments and that utilities are practically free does help.
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