Count : To count means to find out the number of objects by adding one for every object.

Number : A number $x$ is a mathematical symbol representing a quantity.

Division : Division is the mathematical operation that divides objects equally into groups. More generally $x\div y$ is defined as the number that if multiplied by $y$ equals $x.$

Standard algorithm : By standard algorithm we refer to any one of the algorithms that are commonly taught at school to add, subtract, multiply or divide multi-digit numbers such as long division and partial products multiplication.

Equation : An equation is a mathematical statement in which two expressions are written with an equal sign in between. A solution of an equation is a set of variables that makes the statement a true statement.

Positive : Positive means $\geq 0.$

Solution : A solution to an equation is a choice of variables that when substituted into the equation results in a true statement.