IB Maths AA HL SL 4.12 Standardizing normal variables
IB Maths AA HL SL 4.12 Standardizing normal variables
Practise standardising normal variables, using inverse normal values, and solving for thresholds, means or standard deviations from probabilities.
How this is tested
- convert statements like P(W>w)=0.2 to an inverse normal value, then find W
- solve for μ and σ from two probability statements by forming simultaneous equations with z-scores
- use symmetry or a labelled sketch to decide whether the result is z, -z, or central