Activity :Medians of a triangle concur

Median of a triangle is a line segment joining vertex to the mid point of opposite side. There are three medians in a triangle. All medians intersect at a common point called centroid. The centroid always lie in the interior of traingle.

Activity Aim :To verify medians of a triangle concur at a point called centroid which always lie in the interior of the triangle by paper folding.

Material required: Coloured paper , pair of scissors , ruler , stapler.

Procedure :

1. Take a coloured paper and draw any triangle ABC. Cut the triangle.

2. To get the mid point og BC , fold along BC ,such that , B coincides with C .

3. Unfold and mark the mid point of BC as M.

4. Form a crease joining AM.

(AM is a median)

5. Similarly get medians BN and CP by paper folding. What do you observe?

6. Repeat the activity for two more triangles.

Note : The centroid divides each median in the ratio 2:1



Observations:

1. All the medians intersect at a common point called centroid.
2. In all types of triangles , centroid is located in the interior of triangle.

Result : It is verified that the medians of a triangle concur at a point called centroid which always lie in the interior of triangle.

Answer the following:

1. What is a median.
2. How many medians are there in a triangle?
3. What is centroid?
4. Write the property of centroid.