Question

The base edge of a square prism is 15 cm.

The total surface area is 1950 m².

i. What is its height ?

ii. Calculate the volume.

Answer 1

i. Base edge = 15 cm

Total surface area = Base area + Lateral surface area

= 2a² + 4ah (base egde is ‘a’)

1950 = 2 × 15² + 4 × 15 × h

1950 = 450 + 60h

60h = 1950 – 450 = 1500

h = 1500/60 = 25 cm

ii. Volume = a² × h = 15 × 15 × 25

= 5625 cm³