Question

Find the volume of metal required to make a closed box of thickness 1 cm with external measurements 12cmx 7 cmx 10 cm

Answer 1

for external

l=12cm

b=7cm

h=10cm

volume=l*b*h

=12*7*10

=840cm^3

for enternal

l=12-2=10cm

b=7-2=5cm

h=10-2=8cm

volume=l*b*h

=10*5*8

=400cm^3

now

volume of metal=external volume - enternal volume

(840-400)cm^3

=440cm^3