In exchange of example sentences

Similarly, the value of the metal in a five-rupee coin is probably not worth Rs Why then do people accept such notes and coins in exchange of goods which are apparently more valuable than these? The value of the currency notes and coins is derived from the guarantee provided by the issuing authority of these items.Due to differences in resource endowments and labour productivity, countries find it much more advantageous to produce goods and services in which they have cost advantage and trade the surplus in such goods and services with other nations in exchange of goods and services which others can produce more efficiently.