# Practice Exercises
- Calculator – This exercise expands on the original Calculator class to perform subtraction and division with integers.
- Fraction – This exercise expands on the original Fraction class to include methods that allow for adding, subtracting, multiplying, and dividing fractions.
- Square – This exercise expands on the original Square class to include a method that determines the diagonal of a square.
- Coordinate – Not Yet Implemented The Coordinate class represents a geographical co-ordinate for either longitude or latitude. A Coordinate's value can be expressed either as a real number or as degrees, minutes and seconds. It makes use of integer division and overloaded constructors.
- PaintEstimator – The PaintEstimator class is used to estimate the number of paint cans needed for painting a simple room (with or without a window). It makes use of a constant and the Math library; it also uses overloaded constructors.
- BulkItem – The BulkItem class represents products that are available in bulk and shows the cost of individual items. It makes use of rounding (to two decimal places).
- Die - This exercise expands on the original Die class to allow for creating a die of any number of sides, with a default of six sides. This means that there is an overloaded constructor.
- RoundingCalculator – This exercise demonstrates rounding using separate methods for each level of rounding precision.
- GenericRoundingCalculator – This exercise demonstrates rounding to the nearest whole number of fractional number using a couple of "generic" methods.
- PeopleCounter – This simple class is used to count the number of people who have entered a store in a single day. It takes a simplistic approach, counting each person entering and leaving, estimating the number of people for the day by dividing the total count by two.
- ScoreCard – Not Yet Implemented This class represents a scorecard for tracking bowling scores frame by frame. It produces a final tally for the game, as well as the current score and the current frame.
- Cylinder – The Cylinder class represents a cylindrical object whose height and radius is known. The class provides methods to calculate the volume and surface area.
- Cone – The Cone class represents a conical object whose height and base radius is known. The class provides methods to determine the volume and surface area with this information.
- GravityCalculator – The GravityCalculator provides static methods for determining an object's weight for the various planets in our solar system, given the equivalent weight as found on Earth.
- CurrencyCalculator – The CurrencyCalculator allows the conversion of US dollars to four other currencies, given the current exchange rate of those currencies.
For these exercises, compare your results with the unit tests for these classes.