What is the average hexadecimal with a decimal less than 53, an octal less than 61, and a glyph greater than 0?
CREATE TABLE "evolution_of_symbols" (
  "binary" real,
  "octal" real,
  "decimal" real,
  "hexadecimal" real,
  "glyph" real
);
SELECT AVG("hexadecimal") FROM "evolution_of_symbols" WHERE "decimal"<53 AND "octal"<61 AND "glyph">0;