Maximum : The maximum of a set of numbers is the highest of the numbers in the set. A function has a maximum at $x_0$ if $f(x_0)\geq f(x)$ for all $x.$

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

Possible : Possible means having a probability bigger than zero.

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

Square : A square is a quadrilateral with four right angles and four equal length sides. A square is a special case of a rectangle and a special case of a rhombus.

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 $x.$

Favorable outcome : In a random experiment the favorable outcomes are the outcomes of the event of which we want to calculate the probability. For example if we want to calculate the probability of throwing an even number with a dice the favorable outcomes are 2, 4 and 6.

Half : A Half is the number equal to $\frac{1}{2}=0.5.$

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

Possible outcome : Any outcome of a random experiment.

Probability : A probability is a number between 0 and 1 that describes how likely an outcome is. For discrete events that are equally likely the probability can be calculated by dividing the number of favorable outcomes by the number of possible outcomes.

Reduced fraction : A reduced fraction (or simplified fraction or fraction in simplified form or fraction in simplest form) is a fraction $\frac{a}{b}$ such that $a$ and $b$ do not have any common factors bigger than 1. For example the reduced fraction of the fraction $\frac{4}{6}$ is $\frac{2}{3}.$

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

Divisible by 2 : An integer $x$ is called divisible by 2 if $x$ is a multiple of 2. An integer is divisible by 2 if and only if it is even.

Divisible by 3 : An integer $x$ is called divisible by 3 if $x$ is a multiple of 3. An integer is divisible by 3 if and only if the sum of its digits is divisible by 3.

Divisible by 6 : An integer $x$ is called divisible by 6 if $x$ is a multiple of 6. An integer is divisible by 6 if and only if it is even and the sum of its digits is divisible by 3.

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

Set : A set is a collection of objects.

Sum : A sum is the result of an addition.