IB skill practice

Interpret graph degree sums

Use the handshaking lemma to find edge counts or degree totals.

Paper 1, Paper 2 5 marks Difficulty 3

Interpret graph degree sums - exam scenario

A sports academy graph has 9 edges. Use the handshaking lemma to find the sum of all vertex degrees. Enter the requested value and choose the interpretation that matches the result.

Worked practice: result and interpretation

Calculate the requested result first, then choose the interpretation that follows from it.