Dear students ,
Watch this video and do the activity.
To find the area of a circle of given radius by paper folding,cutting and pasting.
Pair of scissors
Step 1 Cut a circle of given radius from the coloured paper.
Step 2 Divide the circle into 16 equal parts by paper folding.
Step 3 Cut 16 parts and arrange them to form a parallelogram.
Step 4 Take the last cutout and again divide it into 2 equal parts.
Step 5 Arrange the 2 parts and the shape in step 3 so that a rectangle is formed.
Step 6 Measure the length & breadth of the rectangle & calculate its area.
We observe that the cutouts of the circle are arranged to form a rectangle.
The length of the rectangle is equal to half of the circumference of the circle and breadth of the rectangle is equal to the radius of the circle.
The area of the circle is calculated using the formula of area of the rectangle.
Length of Rectangle =____________________
Breadth of Rectangle=___________________
Area of Rectangle = ___________________
So, the Area of Circle = _________________
- Mathematics teacher since 1994. After joining teaching profession I realized two things. First one- there is so much which is still to be learned and the second one - there is no standard method for teaching .Each day a new challenge randomly comes forward . For overcoming, there is a need to explore, learn and change. I believe learning is not confined to the four walls of the classroom.Enormous tools are available on the web which may be utilised for making teaching/learning interesting and effective.For me teaching is not just a job,its a passion,a commitment...a mission. Website http://rashmikathuria.webs.com
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