Exchange calculator for carrying out simultaneous currency conversions between three currencies with simple operating keys for users who frequently convert currencies back to an old currency to gain an idea of value

摘要

Calculator comprises a double exchange function in which two exchange calculations can be carried out simultaneously with a presentation of the results in three independent screen zones. For example the screen zones can be divided between Francs, old Francs i.e. pre 1958 Francs and Euros or between Francs, a foreign currency and a Euros.