A First Course in Linear Algebra · Problem SSLE.C53
Systems of Linear Equations — Robert Beezer
Mathematics — Linear Algebra · solving-systems-of-linear-equations
Problem
An article in The Economist (``Free Exchange'', December 6, 2014) quotes the following problem as an illustration that some of the ``underlying assumptions of classical economics'' about people's behavior are incorrect and ``the mind plays tricks.'' A bat and ball cost \$1.10 between them. How much does each cost? Answer this quickly with no writing, then construct system of linear equations and solve the problem carefully.