## Pi: When Students Ask

**Why should I bother learning this?**

Knowing when to use a formula, what formula to use, and how to use a formula correctly are critical factors. Formulas are used in mathematics and science because they save a lot of time and effort. If students understand how a formula is derived, it will help them remember the formula.**Is there any relationship between the area of a circle and the circumference of a circle?**

There is a relationship between the area of a circle and its circumference. If you know the radius, diameter, or circumference of a circle, you can compute the area of a circle. As the radius or diameter of a circle increases, so does the circumference and the area of the circle.**Does equal 3.14?**

No, it doesn't equal 3.14 exactly, but it is very close to that value. Pi is what mathematicians call an irrational number, which means that it cannot be written as a ratio of two whole numbers, , where b 0. The value of 3.14 is a good approximation to , and so is the fraction . Tell your students that they will study more about irrational numbers in high school. Have your students look up more on the Internet about the number pi.