What Is the Exchange Rate Between Pounds, Rubles, and Dollars?

A pound of rubles = a dollar. A joke from the 1990s, as I recall, which came to mind because of the ruble's recent slide. (To be fair, the ruble was worth much less then than now; according to Wikipedia, "The ruble's exchange rate versus the U.S. dollar depreciated significantly from $1 = 125 RUR in January 1992 to approximately $1 = 6,000 RUR when the currency was redenominated in 1998.")