Maths · Co-ordinate of the centroid, orthocentre and circumcentre of a triangle

D, and are the mid-point of sides CA and of then area area

D, \( E \) and \( F \) are the mid-point of sides \( B C \) CA and \( A B \) of \( \triangle A B C, \) then area \( \triangle A B C \) area \( \triangle \mathrm{DEF}= \)

  • A. 4: 1
  • B. 1: 4
  • C. 2: 1
  • D. 4: 3

Step-by-step solution

D, E, F are midpoints of sides BC, CA, AB respectively. Triangle DEF is the medial triangle, which is similar to triangle ABC with scale factor 1/2. The ratio of areas of similar triangles is the square of the scale factor, so area(DEF) = (1/2)^2 * area(ABC) = 1/4 * area(ABC). Hence area(ABC) : area(DEF) = 4:1.
Practise more in this unitView MCQsSign up for full question bank