Graph Theory:Planarity

Question

Q.Suppose that a connected planar simple graph has 20 vertices,each of degree 3.Into how many regions does a representation of this planar graph split the plane ?

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Here I am getting number of faces =36 doesn't it represent the region.?

Comments

20 vertices
30 edges
12 regions {faces which are bounded by edges and one that is outside}

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yes 12, number of edges is 30 using handshaking lemma and then used f = e - v + 2

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Thanks Everyone for the help :)