The side of a triangular plot are in the ratio 3:5:7,it's perimeter is 300 m. Find its area

Answer: 15003 m21500\sqrt{3}\text{ m}^2

Step-by-step solution

Step 1: Find the side lengths using the perimeter

Let the side lengths of the triangular plot be a=3xa = 3x, b=5xb = 5x, and c=7xc = 7x in meters. Since the perimeter is the sum of all three sides, we set their sum equal to 300 m300\text{ m}. Solving this equation gives x=20x = 20, which yields side lengths of 60 m60\text{ m}, 100 m100\text{ m}, and 140 m140\text{ m}.

Step 2: Calculate the semi-perimeter

The semi-perimeter ss is defined as half of the perimeter of the triangle. Dividing the given perimeter 300 m300\text{ m} by 22 gives s=150 ms = 150\text{ m}.

Step 3: Apply Heron's formula

We use Heron's formula to calculate the area of the triangle from its side lengths and semi-perimeter. We first compute the differences: s−a=150−60=90 ms - a = 150 - 60 = 90\text{ m}, s−b=150−100=50 ms - b = 150 - 100 = 50\text{ m}, and s−c=150−140=10weeks  ⟹  10 ms - c = 150 - 140 = 10 weeks \implies 10\text{ m}.

Step 4: Compute the final area

Substituting the values into the formula gives 150×90×50×10\sqrt{150 \times 90 \times 50 \times 10}. We can factor this as (150×50)×(90×10)=7500×900=2500×3×900=50×303=15003 m2\sqrt{(150 \times 50) \times (90 \times 10)} = \sqrt{7500 \times 900} = \sqrt{2500 \times 3 \times 900} = 50 \times 30\sqrt{3} = 1500\sqrt{3}\text{ m}^2.

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