In X∼N(μ,σ2)X\sim N(\mu,\sigma^2)X∼N(μ,σ2), what does the second parameter represent?
An interval probability can be calculated using P(a<X<b)=P(X<b)−P(X<a)\boxed{P(a<X<b)=P(X<b)-P(X<a)}P(a<X<b)=P(X<b)−P(X<a).
The variance, σ2\sigma^2σ2.
Because P(X=20)=0P(X=20)=0P(X=20)=0 for a continuous variable.
z=68−605=\strong1.6z=\frac{68-60}{5}=\strong{1.6}z=568−60=\strong1.6.
2.4.6 Probabilities using the normal distribution (A-level only) Flashcards
Flashcards for OCR A Level Maths 2.4.6 Probabilities using the normal distribution (A-level only), covering the key formulae, methods and definitions you need to recall for Paper 1, Paper 2 and Paper 3. 20 cards, matched to the OCR A Level Maths (H240) specification. Recall questions account for roughly 50% of marks at A Level Maths, so these target the marks you can secure before the paper starts.