Convert from bag [portland cement] to libra [ancient Rome]

Unit Definition (bag [portland cement])
The bag [portland cement] is a unit of weight for cement. Traditionally a bag of portland cement weighs 94 pounds (42.6 kilograms) in the US. and 87.5 pounds (39.7 kilograms) in Canada. However, cement is now being sold also in metric-sized bags of 50 kilograms (110.2 pounds) by many suppliers.

Unit Definition (libra [ancient Rome])
The libra [ancient Rome] is a traditional unit of weight. The libra was the Roman unit from which the English pound is descended; the symbol "lb" for the pound comes from this unit. The Roman libra contained only 12 unciae (ounces) and was about 0.722 English pound. The word "libra" is sometimes used now for the kilogram, a much larger unit.