A closed box is made up of wood which is lcm thick. The outer dimensio

1.	A closed box is made up of wood which is lcm thick. The outer dimensions of the box is5 cm x 4 cm x 7 cm. Find the volume of the wood used.
Answer» Answer: GIVEN, OUTER length =5 CM Outer breadth =4 cm Outer HEIGHT =7 cm $\sf{Outer \ volume=length×breadth×height}$ $\sf{=5×4×7=140cm^{3}}$ $\sf{Thickness \ of \ wooden \ box, w=1 cm}$ $\sf{Inner \: length =l-2w=5-2=3 cm}$ $\sf{Inner \ breadth =b-2w=4-2=2 cm}$ $\sf{Inner \ height =h-2w=7-2=5 cm}$ $\sf{Inner \ volume =3×2×5=30cm^{3}}$ $\sf{Volume \ of \ wood \ used = outer \ volume - inner \ volume}$ $\sf{=140-30=110cm^{3}}$ $\\$