The sides of a triangle are 11 cm, 60 cm and 61 cm. What is the area of the triangle formed by joining the mid-points of the sides of the triangle?
- A. 165 cm^2
- B. 110 cm^2
- C. 82.5 cm^2 ✓
- D. 72.5 cm^2
Correct Answer: C. 82.5 cm^2
Explanation
The triangle is a right-angled triangle because 11^2 + 60^2 = 121 + 3600 = 3721 = 61^2. The area of the main triangle is \frac{1}{2} \times 11 \times 60 = 330 cm^2. The area of the triangle formed by the mid-points is \frac{1}{4} of the original area, which is \frac{330}{4} = 82.5 cm^2.
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