Question

The volume vof a cuboid is 3600 cm and its height is 12 cm . If the lenght is 3/4 of the breadth, then find the total surface area of the cuboid.

Answer 1

Answer:

Step-by-step explanation:

volume of cuboid= l*w*h

h= 12cm

b=b

l=$\frac{3b}{4\\}$

vol. of cuboid=3600

=12*b*3b/4

⇒36b²/4

⇒9b²=3600

⇒b²=400

⇒b=20

∴l=15cm          -----(l=3b/4)

surface area of cube= 2lb+2lh+2hb

⇒2(15)(20)+2(15)(12)+2(12)(20)

⇒600+360+480

⇒1440cm

Answer 2

let the breadth be X.

So,

x × 3x/4 × 12 = 3600

3x^2/4 × 12 = 3600

9x^2 = 3600

x^2 = 400

x = 20

Now, Breadth=20

Length=15

Height=12

Therefore, total surface area=2[(20×15)+(15×12)+(12×20)]

=2(300+180+240)

=2×720

=1440.

I think that it will help.