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Find the length of the largest pole that can be placed in a room of dimensions 12 m × 4 m × 3 m.

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Question

Find the length of the largest pole that can be placed in a room of dimensions 12 m × 4 m × 3 m.

Sum
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Solution

We have ΔACF, in which ∠C = 90°, CF = 3 m and AC = `sqrt((12)^2 + (4)^2)` m

The length of the largest pole = Length of diagonal of cuboid

⇒ (AF)2 = (AC)2 + (CF)2

⇒ (AF)2 = (12)2 + (4)2 + (3)2

⇒ `AF = sqrt(144 + 16 + 9)`

= `sqrt(169)`

= 13 m

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Chapter 11: Mensuration - Exercise [Page 353]

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NCERT Exemplar Mathematics [English] Class 8
Chapter 11 Mensuration
Exercise | Q 75. | Page 353

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