Question

the external dimensions of a closed wooden box are 25cm×23cm×18cm. If the thickness of the wood used is 2cm,find the total inner surface of the box​

Answer 1

Answer:

For wooden box

External length=25 cm

External breath=21 cm

And,External height=13 cm

So,external volume=(25×21×13)cm^3=6825cm^3

Thickness=1.5 cm

So,Internal length=25-(1.5×2)=22cm

Internal breadth=21-(1.5×2)=18cm

Internal height=13-(1.5×2)=10cm

So,Internal volume=(22×18×10)cm^3=3960cm^2

1) Now,Volume of wood=External volume-Internal volume

=6825-3960=2865cm^3

2) Rate=Rs.1.50 per cm^3

And,volume=2865cm^3

So,Cost=Rs.(2865×1.50)=Rs.4297.5

3) Volume of cube=(side)^3=(5)^3cm^3=125cm^3

No. of cube=Internal volume/volume of 1 cube

=(3960/125)=31.68cubes

hope it's helpful☺️