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

Count up by 7 starting at 2.

The correct answer is 9. $2+7=9.$

Angle : If two line segments (or rays) both start at a common point the opening between the two line segments is called an angle. The common point is called vertex of the angle. The size of an angle is measured in degrees.

Corner : A corner of a shape is a point in the shape such that this point does not lie on the line segment between any two other points in the shape. Every triangle has 3 corners and every quadrilateral has 4 corners.

Degree : For angles one degree is defined as the angle represented by a $\frac{1}{360}$ of the angle represented by a full circle. For measuring temperatures one can use either degrees Celsius or degrees Fahrenheit. In a polynomial the degree describes the highest exponent of $x$ that has a non-zero coefficient. For example the degree of $1+x+x^2$ is 2.

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 $x.$

Hexagon : A hexagon is a polygon with six corners. The sum of the angles in a hexagon is $720^{\circ}.$

Interior angle : An interior angle at the crossing of two parallel lines by a third line means any of the angles between the two parallel lines. An interior angle of a polygon is any of the angles at any of the corners of the polygon that lies within the polygon.

Line : A line AB is a one-dimensional shape that includes the points A and B, all the points on the line segment in between A and B and all the points of the straight extension of the line segment beyond A and B. A line does not have an endpoint.

Regular polygon : A polygon is called regular if it is convex, equilateral and equiangular.

Sum : A sum is the result of an addition.

Triangle : A triangle is a polygon with three corners and three sides. You can calculate the area of a triangle by multiplying half the length of the base by the height on that base. The sum of the interior angles in a triangle is always $180^{\circ}.$

Divide the hexagon into triangles and use that the sum of angles in a triangle is 180 degrees.

The correct answer is 720. Pick any corner of the hexagon and draw lines from every corner of the hexagon to this corner. This will dissect the hexagon into 4 triangles and the sum of the angles of the hexagon equals the sum of the angles in the 4 triangles. Because every triangle has an angle sum of 180 degrees, the angle sum in the hexagon is 4 times 180=720 degrees.

Area : The amount of unit squares that is needed to cover a 2-dimensional shape.

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 $x.$

Inch : An inch or $in$ is a unit of measurement for length. 12 inches are one foot and 1 inch is about 2.54 $cm.$

Length : Length is the attribute of a one-dimensional shape that can be measured with a measuring tape.

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

Rectangle : A rectangle is a quadrilateral with 4 right angles. Two opposing sides in a rectangle have the same length. They are sometimes referred to as the width and the length of the rectangle. To calculate the area of an rectangle one can multiply the width of the rectangle by the length of the rectangle. A square is the special case of a rectangle in which all side lengths are the same. Every rectangle is a parallelogram.

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 $\frac{2}{3}.$

Square inch : Square inch is a unit of measurement for measuring area. 1 square inch is the area of a square with side length 1 inch. 144 square inches are 1 square foot.

Two thirds : Two thirds refers to the number $\frac{2}{3}=0.\overline{6}.$

To get the width you have to divide the area of the rectangle by its length.

The correct answer is 2/5. The area of a rectangle is calculated by multiplying the width of the rectangle with the length of the rectangle. This means that you can calculate the width of a rectangle by dividing the are by its length: $\frac{4}{15}\div \frac{2}{3}=\frac{4}{15}\cdot \frac{3}{2}=\frac{2}{5}.$