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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

Correct Answer:


B) 52 cm

Description for Correct answer:
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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