a statistical value in an ordered set of values below and above which there is an equal number of values, or which is the arithmetic mean of the two middle values if there is no one middle value

a vertical line that divides the histogram (type of graph) of a frequency distribution (frequency with which values of a variable occur) into two parts of equal area

a line from a point of intersection of two sides of a triangle to the midpoint of the opposite side

a line joining the midpoints of the nonparallel sides of a trapezium