# Congratulations! # You discovered Pi yesterday.  If each object was measured with 100% accuracy, the ratios of circumference to diameter would have all been exactly the same.

## When using pi in class work we can get away with using 3.14.  But when you graduate to building spaceships, where being off by a hair in a measurement can cause a shuttle to burn up on re-entry, the accuracy of keeping all of the decimals in pi can save lives.  # Study the videos and pictures below:   # Take note:

## Area is the amount of space there is on a flat surface.  The size of a house (square feet), a piece of land (acres), wrapping a present (how much paper do you use?); These are all times when we need to calculate area. ## When we calculate areas of shapes with straight lines, we can use formulas that will help us score the answer efficiently:  ## When we are looking to find the area of a curved surface it gets a little tricky.  Use the gridlines to estimate the circles below, try a find a relationship between 3.14, radius and the area of a circle.    BIG DEAL HERE:

## Look at your estimates of the area and try and find how the radius and 3.14 (∏) could be factors in this equation. 