Question

25 identical cubical wooden blocks are to be painted on all sides. if the total cost of painting at rate of Rs.12 per cm square is rs.129600,find measure of the edge of one wooden block.

Answer 1

Answer:

Step-by-step explanation:

Cost = 12 × 6a^2 = 129600

=> a^2 = 129600/12 × 6

=> a^2 = 1800

=> a = √1800

= 42.42...

Answer 2

ANSWER


GIVEN

Number of cubical box= 25


$cost \: \: of \: one \: cubical \: box = \frac{129600}{25}$



$cost \: of \: one \: cubical \: box = 5,184$



$surface \: area \: of \: a \: cube \: = \frac{5184 }{12}$



$surface \: area \: of \: a \: cube = \: 432 {cm}^{2}$




$surface \: \: area \: of \: cube = 6 {a}^{2}$



so,


$6 {a}^{2} = 432$


${a}^{2} = \frac{432}{6}$

${a}^{2} = 72$


$a = 6 \sqrt{2} cm$


or a= 8.48 cm




HENCE


edge of wooden block= 8.48 cm

or

$6 \sqrt{2} cm$