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

Digit : A digit is a symbol used in the representation of a number.

Divisible : An integer $x$ is called divisible by an integer $y$ if the division $x:y$ has a remainder of zero. For example 4 is divisible by 2 but 5 is not divisible by 2.

Divisible by 4 : An integer $x$ is called divisible by 4 if $x$ is a multiple of 4. An integer is divisible by 4 if and only if the last two digits form a number that is divisible by 4.

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

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.

Multiplication : Multiplication is the mathematical operation that is a shorthand for adding the same amount several times. For example $3\cdot 4=4+4+4=12.$

Parenthesis : Parenthesis or brackets are used to clarify the order of operations in an expression. Within an expression terms in parenthesis are supposed to be calculated first. For example $2\cdot(3+4)=2\cdot 7=14$ but $2\cdot 3+4=6+4=10.$

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