9. A closed box is made of wood which is 1.8 cm thick. Its external
dimensions are 84 cm x 64 cm x 50 cm. Find:
(i) the capacity of the box.
(i) the volume of the wood used in making the box.
(iii) the weight of the empty box if 1 cm'of wood weighs 6.8
g.
Answers
Answer:
Step-by-step explanation:
external length = 84 cm
external breadth = 64 cm
external height = 50 cm
thickness = 1.8 cm
internal length = 84- 2(1.8) = 84- 3.6 = 80.4 cm
internal breadth =64- 2(1.8) = 64-3.6 = 60.4
internal height= 50- 2(1.8) = 50 - 3.6 = 46.4 cm
capacity of the box = length ×breadth× height
= 80.4 × 60.4 ×46.4
= 225325.824 cm³
The volume of the wood used in making the box. = external volume - internal volume
= (84×64×50) - 225325.824
= 268800 - 225325.824
= 43474.176 cm³
if 1cm cube of wood weighs= 6.8 gm
then
43474.176 cm³of wood weighs = 43474.176 cm³× 6.8 = 295624.39 gm
hence ,
capacity of the box =225325.824 cm³
The volume of the wood used in making the box. =43474.176 cm³
the weight of the empty box = 295624.39 gm