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# The whole surface area of a rectangular block is 8788 sq cm. If length, breadth and height are in the ratio of 4 : 3 : 2, then find the length.

 A) 26 cm B) 52 cm C) 104 cm D) 13 cm

 B) 52 cm

Let length. breadth and height be 4x, 3x and 2x respectively.

Whole surface area = $$\Large 2 \left(lb+bh+lh\right)$$

=> $$\Large \left(lb+bh+lh\right) = \frac{8788}{2} = 4394$$

$$\Large \left(4 \times 3 + 3 \times 2 + 2 \times 4\right)x^{2} = 4394$$

=> $$\Large 26x^{2} = 4397$$

=> $$\Large x^{2} = 169 => x = 13$$

Therefore, Length = $$\Large 4x = 4 \times 13 = 52 cm$$

Part of solved Volume and surface area questions and answers : >> Elementary Mathematics >> Volume and surface area

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