Question

14. The sum of length, breadth and height of a cuboidal room is 26 m and the length of its
or is HOTS
diagonal is 20 m. Find the total surface area of cuboid.​

Answer 1

≡QUESTION≡

The sum of length, breadth and height of a cuboidal room is 26 m and the length of its diagonal is 20 m. Find the total surface area of cuboid.

                                                     

║⊕ANSWER⊕║

Sum of length, breadth, and height of a cuboidal room is 26 m

l + b + h = 26 m

And length of it's diagonal is 20 m

$l^{2} + b^{2} + h^{2} = 20^{2}$

$2 (lb + bh + hl) = ?$

$26^{2} - 2(lb + bh + hl) = 400 [from (1)]$

$676 - 2(lb + bh + hl) = 400\\676 - 400 = 2(lb + bh + hl)276 \\2(lb + bh + hl) = 276$

∴ Total surface area of the cuboid = 276 cm²