Question

Diagonal of a cuboid whose dimension are 21cm X 16cm X 12cm is:- a) 19cm, b) 29cm , c) 21cm. ​

Answer 1

Step-by-step explanation:

Diagonal of cuboid=(l^2+b^2+h^2)^1/2

=(21^2+16^2+12^2)^1/2

=841^1/2

=29

Answer 2

$\underline{\pink { Dimensions \: of \:a \:cuboid :}}$

Length (l) = 21 cm,

Breadth (b) = 16 cm ,

Height (h) = 12 cm

$\boxed {\blue { Diagonal (d) = \sqrt{l^{2} + b^{2} + h^{2} }}}$

$d = \sqrt{ (21)^{2} + (16)^{2} + (12)^{2}}\\= \sqrt{441 + 256 + 144 }\\= \sqrt{841}\\= \sqrt{(29)^{2}}\\= 29$

$Diagonal (d) = 29\:cm$

Therefore.,

$Option \green { ( b ) } \:is \: correct .$

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