The perimeter of a triangular field is 540 m, and it side are in the ratio 25:17:12.Find the area of the field also find the cost of ploughing the field at rupees 40 per 100m
Answers
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The perimeter of a triangular field is 540 m, and its sides are in the ratio 25:17:12. Find the area of the field. Also, find the cost of ploughing the field at RS 40 per 100m².
Solution -
Perimeter of triangle =540m
Perimeter of triangle =540mLet the sides of triangle be a, b and c.
On dividing 540 m in the ratio 25:17:12, we get
a=25xcm
b=17xcm
c=12xcm
we know that, perimeter of a triangle = Sum of all sides =a+b+c
540=25x+17x+12x
540=54x
x=10
Sides are:
a=25x=250cm
b=17x=170cm
c=12x=120cm
Let a, b and c be the sides of a triangle.
Let a, b and c be the sides of a triangle.Apply Heron's Formula of find the area of triangle.
Area = √S(S−a)(S−b)(S−c)
Where S = a+b+c / 2
S = 1 / 2 (250+170+120) = 270m
Area = √ (270 (270−250) (270−170) (270−120))
= √(270×20×10×150)
= 9000
Area of triangle is 9000m ²
Now,
The cost of ploughing 100m² =Rs 40
The cost of ploughing 1m² = Rs 40 / 100
Therefore, cost of ploughing 9000m ² =9000× ( 40 / 100 ) = Rs 3600
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I hope this helps you....
Correct question:
The perimeter of a triangular field is 540 m, and its sides are in the ratio 25:17:12. Find the area of the field also, find the cost of ploughing the field at rupees 40 per 100m sq.
Given:
- The perimeter of a triangle is 540 m
- The ratio of the sides of the triangle is 25:17:12
To find:
The area of the field
Also the cost of ploughing the field at Rs. 400 per 100m
Now,
Let the sides of the triangle be
- a = 25x m
- b = 17x m
- c = 12x m
So,
The perimeter of a triangle is = sum of all three sides
⇒ 25x + 17x + 12x = 540
⇒ 54x = 540
⇒ x = 540 ÷ 54
[By taking 54 to RHS]
⇒ x = 10
∵ Thus, the value of x = 10
Now,
The side of the triangle is
- a = 25x = 25*10 = 250 m
- b = 17x = 17*10 = 170 m
- c = 12x = 12*10 = 120 m
Finding the area of the field
[In which 'S' is 'half of the perimeter', and (a, b, c) are the side of the triangle.]
S = 540 ÷ 2
S = 270
= 3*2*2*5*5*3*5*2
= 9000 m sq.
Now,
- Ploughing is done in → the area.
The cost of ploughing the field at Rs 40 per 100m
100 m sq. = Rs 40
1m sq. = Rs 0.4
Now,
The cost of ploughing the field at 9000 m sq. is
= 9000 * 0.4 = Rs 3600
Hence,
- The area of the field if 9000 m sq.
- The cost of ploughing the field is Rs. 3600