Question:
Given an equilateral triangle T1 with side 24 cm, a second triangle T2 is formed by joining the midpoints of the sides of T1. Then a third triangle T3 is formed by joining the midpoints of the sides of T2. If this process of forming triangles is continued, the sum of the areas, in sq cm, of infinitely many such triangles T1, T2, T3,... will be

  1. \(164\sqrt 3 \)
  2. \(188\sqrt 3 \)
  3. \(248\sqrt 3 \)
  4. \(192\sqrt 3 \)
Show Answer
Correct Answer: 4

Any equilateral triangle formed by joining the midpoints of the sides of another equilateral triangle will have its side equal to half the side of the second equilateral triangle.
Side of T1 = 24 cm Side of T2 = 12 cm Side of T3 = 6 cm and so on.
Sum of the areas of all the triangles
$=\frac{\sqrt{3}}{4}\left(24^{2}+12^{2}+6^{2}+\ldots \ldots\right)$
$=\frac{\sqrt{3}}{4}\left(\frac{576}{1-\frac{1}{4}}\right)=192 \sqrt{3}$


CAT Online Course
Also Check: 841+ CAT Quant Questions with Solutions

CAT 2018 Slot-1


CAT 2018 Slot-2


CAT Quant Questions with Video Solutions

30 must do CAT Quant Questions with Video Solutions