Question

3. The cost of fencing a rectangular field at the rate of 10 per metre is 700. Find the perimeter and
breadth of rectangular field whose length is 15 m.​

Answer 1

$\displaystyle\large\underline{\sf\red{Given}}$

✭ The cost of fencing a rectangular field at the cost of 10 per meter is 700

✭ Length of the field is 15 m

$\displaystyle\large\underline{\sf\blue{To \ Find}}$

◈ The breadth of the field?

$\displaystyle\large\underline{\sf\gray{Solution}}$

Perimeter of a rectangle is given by,

$\displaystyle\underline{\boxed{\sf Perimeter_{Rectangle} = 2(l+b)}}$

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$\underline{\bigstar\:\textsf{According to the given Question :}}$

The perimeter of the field will be,

➝ $\displaystyle\sf Perimeter = \dfrac{Total \ cost}{Cost \ per \ m^2}$

➝ $\displaystyle\sf Perimeter = \dfrac{700}{10}$

➝ $\displaystyle\sf\orange{Perimeter = 70 \ m}$

So then the breadth will be,

➳ $\displaystyle\sf Perimeter_{Rectangle} = 2(l+b)$

➳ $\displaystyle\sf 70 = 2(15+b)$

➳ $\displaystyle\sf 70 = 30+2b$

➳$\displaystyle\sf 70-30 = 2b$

➳ $\displaystyle\sf 40 = 2b$

➳ $\displaystyle\sf \dfrac{40}{2} = b$

➳ $\displaystyle\sf \pink{Breadth = 20 \ m}$

$\displaystyle\sf \therefore\:\underline{\sf Breadth \ of \ the \ triangle \ is 20 m}$

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