Question

A rectangular sheet of metal which measures 120cm by 0.8m is 1.5mm thick and is made of material whose density is 2.2 g/cm³. From each of the four corners of the rectangle, a square of side 10cm is cut off and the remaining part folded to form an open cuboid.

1. calculate
   1. the capacity of the cuboid in cm³ to the nearest whole number 
   2. the mass of the empty cuboid in kg to the nearest whole number 
2. the cuboid is filled with a liquid whose density is 0.75g/cm³. Calculate the mass in kg of the cuboid when full of the liquid 
3. calculate the mass of metal lost in kg

Answer 1

1.  
   1. 99.7 × 59.7 × 9.85   
      =58628cm³               
   2. Outer volume = 100 × 60 × 10
                                    =  60,000
      Inner volume         =−58,628         
      Volume of material    1372cm³     
      Mass = 1372 × 2.2  =3kg             
                      1000
2. Mass of liquid
   =0.75 × 58628 = 43.971kg  
            1000
   Total mass = 46.971kg         
3. Volume = 4 × 10 × 10 × 0.15    
   =60cm³
   Mass = 60 × 2.2 =132g