Question

Volume of the bricks is 3000cm cube and its dimension are in the ratio 3:2:4.If the entire surface is painted at 50paisa per cm square,the cost will be

Answer 1

$\bold{Given}\begin{cases}\sf{Volume=3000\:cm^{3}}\\\sf{Dimension=3:2:4}\end{cases}$

$\bold{\boxed{\huge{\boxed{\orange{\small{\boxed{\huge{\red{\bold{\:Answer}}}}}}}}}}$

$\green{\bold{Let\:sides\:of\:bricks\:are\:3x\:2x\:4x}}$

we know that, volume of bricks =

$\large\red{\boxed{\sf l*b*h}}}$

so,

3x×4x×2x = 3000

24x³ = 3000

x³ = 125

x = 5

so, sides are = 15cm,10cm and 20cm

Now,

we know that ,

surface area of cuboid is given by :-------

$2(l \times b + b \times h + h \times l)$

putting values we get,

surface area = 2(15*10+10*20+20*15)

surface area = 2(150+200+300)

surface area = 2(650)

surface area = 1300cm²

so,

cost of painting the surface area will be = 1300×0.5 = $\huge\underline\purple{\mathcal Rs.650}$

$\huge\underline\mathfrak\green{Hope\:it\:Helps\:You}$