Activity: Find an Approximate Value For Pi You can read about π
(Pi) first You will need: Draw a circle on your card. The exact
size doesn't matter, but let's use a radius of 5 cm. Use your
protractor to divide the circle up into twelve equal sectors.
What will be the angle for each sector? That's easy – just
divide 360° (one complete turn) by 12: So each of the angles
must be 30° Divide just one of the sectors into two equal parts
– that's 15° for each sector. You now have thirteen sectors –
number them 1 to 13: Cut out the thirteen sectors using the
scissors: Rearrange the 13 sectors like this (you can glue them
onto a piece of paper): Now that shape resembles a rectangle:
What are the (approximate) height and width of the rectangle?
Its height is the circle's radius: just look at sectors 1 and 13
above. When they were in the circle they were "radius" high. Its
width (actually one "bumpy" edge), is half of the curved parts
along the edge of the circle ... in other words it is about half
the circumference of