Question

Find the volume of wood used to make a closed rectangular box of outer dimensions 60 cm by 45 cm by 32 cm, the thickness of wood being 2.5 cm all around. Also find the capacity of the box.

Answer 1

Shubha answered this
745 helpful votes in Math, Class XI-Science
Water pumped out 8400 litre = 8400/ 1000 = 8.4 cubic meter

Surface area of tank =LxB = 7m x 6m = 42 sq mtr

Therefore decrease in level = 8.4 / 42 = 0.2 mtr (Answer

Answer 2

Step-by-step explanation:

External length = 60 cm, external breadth = 45 cm and external height = 32 cm.

External volume =$(60 \times 45 \times 32) {cm}^{3 } = 86400 {cm}^{3}$

Internal length = $60 - (2.5 \times 2) \: cm = (60 - 5) \: cm = 55 \: cm$

Internal breadth ={45-(2.5×2) cm=(45-5)cm=40 cm

Internal height = {32-(2.5×2)} cm = (32-5)cm=27 cm

Internal volume = $(55 \times 40 \times 27) {cm}^{3} = 59400 \: {cm}^{3}$

∴ capacity of the box = internal volume =$59400 {cm}^{3}$

and volume of wood used to make the box = (external volume)-(internal volume)

= $(89400 - 59400) {cm}^{3} = 27000 \: {cm}^{3}$