Complete the table by using Euler’s formula.

(i) Given: Faces = 8

Vertices = 6

Edges = ?

According to Euler’s formula, we know that : F + V = E + 2

∴ 8 + 6 = E + 2

⇒ 14 = E + 2

⇒ E = 14—2 = 12

∴ No. of Edges = 12

(ii) Given: Faces = 5

Vertices = ?

Edges = 9

According to Euler’s formula, we know that : F + V = E + 2

∴ 5 + V = 9 + 2

⇒ 5 + V = 11

⇒ V = 11—5 = 6

∴ No. of Vertices = 6

(iii) Given: Faces = ?

Vertices = 12

Edges = 30

According to Euler’s formula, we know that : F + V = E + 2

∴ F + 12 = 30 + 2

⇒ F + 12 = 32

⇒ E = 32—12 = 20

∴ No. of faces = 20