Mensuration

Question
CBSEENMA8003414

Describe how the two figures at the right are alike and how they are different. Which box has larger surface area?

Solution

Similarity:  Both have the same height.
Difference : Cylinder has curved and circular surfaces.
               Cube : All faces are identical squares.
Lateral surface area of the cylinder = space 2 πrh
                                                       = 2 cross times 22 over 7 cross times 7 over 2 cross times 7 space space cm squared
                                                       = 7 space cross times space 22 space cm squared
                                                     equals space 154 space cm squared   
Lateral surface area of the cube = 4l2
                                                   = 4 x (7 x 7) cm2
                                                   = 4 x 49 cm2
                                                   = 196 cm2
Obviously the cubical box has larger surface area.