Question

a closed box of uniform thickness is made of wood 1cm thick. Its extenal dimensions are 6cm and 5 cm by 4 cm. Find the
a. volume of the wood used in making the box.
b. the capacity of the box, given that the cover is full length and full width
c. The interior surface area if the box is left open

Answer 1

I assume the height of 4 cm includes the cover
outside box is 6 x 5 x 4
inside it is 4 x 3 x 2

volume outside = 120
volume inside = 24 (b)
so volume wood = 120 - 24 = 96 (a)

length = 4
width = 3
depth = 2 -1 for cover = 1
so area bottom inside = 4*3 = 12
area sides = 2*4*1 = 8
area ends = 2 *3 * 1 = 6
so
12 + 8 + 6 = 26