A wire which was used to form a square of side 30 cm is divided into 3...
The length of the wire = 4*30 = 120 cm.
Let 'x' be the length of the smallest part of the wire.
Length of the longest part = x + 20
Length of the second longest part*1.25 = Length of the longest part
⇒ Length of the second longest part = 0.8*Length of the longest part
⇒ x + 20 + 0.8*(x+20) + x = 120
⇒ x + 20 + 0.8x + 16 + x = 120
2.8x + 36 = 120
2.8x = 84
⇒ x = 30 cm
The sides of the triangle are 30 cm, 40 cm, and 50 cm.
We can see that the sides of the triangle form a Pythagorean triplet.
Therefore, the area of the triangle is 0.5*30*40 = 600 cm2
Therefore, option D is the right answer.
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A wire which was used to form a square of side 30 cm is divided into 3...
Given:
- A wire is used to form a square of side 30 cm.
- The wire is divided into 3 parts.
- The length of the longest part is 25% more than the length of the second longest part.
- The shortest part is 20 cm shorter than the longest part.
To find:
- The area of the triangle formed by these three parts.
Solution:
Let the length of the second longest part be x cm.
According to the given information:
- The length of the longest part = x + 25% of x = x + (25/100)x = (5/4)x
- The shortest part = length of the longest part - 20 cm = (5/4)x - 20 cm
Since the wire is used to form a square of side 30 cm, the sum of the lengths of the three parts should be equal to the perimeter of the square.
Perimeter of the square = 4 * side = 4 * 30 cm = 120 cm
Therefore, we can write the equation as:
x + (5/4)x + (5/4)x - 20 = 120
Simplifying the equation:
(9/4)x - 20 = 120
(9/4)x = 140
x = (4/9) * 140
x = 62.22 cm (approx)
Calculating the lengths of the three parts:
Length of the second longest part = x = 62.22 cm (approx)
Length of the longest part = (5/4)x = (5/4) * 62.22 cm = 77.78 cm (approx)
Length of the shortest part = (5/4)x - 20 = 77.78 - 20 = 57.78 cm (approx)
Calculating the area of the triangle:
To find the area of the triangle, we need the lengths of its three sides.
Using Heron's formula, the area of a triangle with sides a, b, and c is given by:
Area = √(s(s-a)(s-b)(s-c))
Where s is the semi-perimeter of the triangle.
Semi-perimeter, s = (a + b + c)/2
Substituting the values of a, b, and c:
Semi-perimeter, s = (62.22 + 77.78 + 57.78)/2 = 97.39 cm (approx)
Area = √(97.39(97.39-62.22)(97.39-77.78)(97.39-57.78))
= √(97.39 * 35.17 * 19.61 * 39.61)
= √(135,634.11)
= 368.40 cm² (approx)
Therefore, the area of the triangle formed by the three parts is approximately 368.40 cm², which is not given as an option. So, the correct answer cannot be determined from the given options.
A wire which was used to form a square of side 30 cm is divided into 3...
The length of the wire = 4*30 = 120 cm.
Let 'x' be the length of the smallest part of the wire.
Length of the longest part = x + 20
Length of the second longest part*1.25 = Length of the longest part
⇒ Length of the second longest part = 0.8*Length of the longest part
⇒ x + 20 + 0.8*(x+20) + x = 120
⇒ x + 20 + 0.8x + 16 + x = 120
2.8x + 36 = 120
2.8x = 84
⇒ x = 30 cm
The sides of the triangle are 30 cm, 40 cm, and 50 cm.
We can see that the sides of the triangle form a Pythagorean triplet.
Therefore, the area of the triangle is 0.5*30*40 = 600 cm2
Therefore, option D is the right answer.
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