Changes

'''Pi''' is the name for the Greek letter <big><big><math>\pi</math></big></big>, which corresponds to the English letter '''p.'''  

'''Pi''' is the name for the Greek letter <big><big><math>\pi</math></big></big>, which corresponds to the English letter '''p.'''  

<big><math>\pi</math></big> is also the symbol used in mathematics for the ratio between the diameter of a circle and its circumference, and which appears in many other places.   

<big><math>\pi</math></big> is also the symbol used in mathematics for the ratio of the circumference of a circle to its diameter, which turns out to be a very important number, appearing in many formulations of mathematics and physics.   

<big><math>\pi</math></big> is an [[irrational number]]; this means that it cannot be expressed as a fraction, and (therefore) cannot be expressed exactly as a decimal no matter how many decimal places it is carried out to.  

<big><math>\pi</math></big> is an [[irrational number]]; this means that it cannot be expressed as a fraction, and (therefore) cannot be expressed exactly as a decimal no matter how many decimal places it is carried out to.