The length and the b readth of a rectangle are in the ratio 7 : 5 . W ...
Let the length and the breadth be lx and 5x respectively.
The new area of the rectangle = (7x + 5) x (5x - 3) = 35x2 + 4x - 15
From the given condition, 35x2 + 4x - 15 = 35x2 - 4
x = 2.75 units
The p erim eter o f the rectangle =12x2x2.75 units = 66 units
Answer: 66
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The length and the b readth of a rectangle are in the ratio 7 : 5 . W ...
Given information:
The length and the breadth of a rectangle are in the ratio 7:5.
Let's assume:
Let the length of the rectangle be 7x and the breadth be 5x.
Given condition:
When the length of the rectangle is increased by 5 units and the breadth is decreased by 3 units, the area decreases by 4 sq. units.
Calculating the original area:
The original area of the rectangle is given by A = length * breadth.
So, the original area is (7x) * (5x) = 35x^2.
Calculating the new area:
According to the given condition, the new length is (7x + 5) and the new breadth is (5x - 3).
The new area of the rectangle is (7x + 5) * (5x - 3) = 35x^2 - 6x - 15.
Calculating the difference in areas:
The difference in areas is given by the original area minus the new area:
35x^2 - (35x^2 - 6x - 15) = 6x + 15.
Given condition:
The difference in areas is 4 sq. units.
So, 6x + 15 = 4.
Solving for x:
6x = -11.
x = -11/6.
Since the length and breadth cannot be negative, we discard the negative value of x.
Calculating the perimeter:
The perimeter of the rectangle is given by P = 2(length + breadth).
Substituting the values, we get:
P = 2(7x + 5x) = 2(12x) = 24x.
Using the value of x:
P = 24 * (-11/6) = -44.
Again, since the perimeter cannot be negative, we discard the negative value.
Final answer:
Hence, the perimeter of the original rectangle is 66 units.
The length and the b readth of a rectangle are in the ratio 7 : 5 . W ...
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