IB skill practice

Use normal linear combinations

Calculate mean or standard deviation of a linear combination of normal variables.

Paper 1, Paper 2 5 marks Difficulty 5

Use normal linear combinations - exam scenario

Independent normal variables in a regional clinic have means 51 and 30. Find the mean of their sum. 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.