Complex sentence: Banknotes up to 50 cruzeiros of the previous series were replaced by coins by 1984 and 10,000 and 50,000 cruzeiro banknotes were introduced, followed by 100,000 cruzeiros in 1985, by which time notes up to 500 cruzeiros had been replaced by coins.
Split into simpler sentences: Banknotes up to 50 cruzeiros of the previous series were replaced by coins by 1984. In 1984,10,000 and 50,000 cruzeiro banknotes were introduced, followed by 100,000 cruzeiros in 1985, by which time notes up to 500 cruzeiros had been replaced by coins.