Question

inner dimensions of an open wooden box are 65cm×45cm×30cm and it is made of 2.5 cm thick wood. find the capacity of the box. also find the weight of the box in kg if 60 cubic cm wood weights 9 grams

Answer 1

 Given : Length = 65 cm, Breadth = 45 cm, Height = 30 cm

Now, the capacity of the box will be equal to the inner volume of the box.
( length × breadth × height)

Hence, the inner volume(capacity) = (65 ×45 × 30) cm3 = 87750 cm3

Now ,it has been also given that the thickness of wood is 2.5 cm
Hence, the outer length will be 65+(2.5 + 2.5) = 70 ........(since the thickness is from both sides of inner length)

Similarly, the outer breadth will be 45+(2.5 +2.5) = 50 cm
& the outer height will be 30+(2.5 +2.5) = 35 cm

Hence, the outer volume of the box will be = (70 × 50 ×35) cm3 = 122500 cm3

Hence, the volume of block used = (122500 - 87750)cm3 = 34750 cm3

Now, 60cm3 of wood weighs = 9 gms
1cm3 of wood weighs = 9/60
114700cm3 of wood weighs =(9×34750) /60 = 5212.5 gms or 5.2125 kgs

So, the inner capacity of box is 87750 cm3 and the weight of box is 5.2125 kgs