Pearson Edexcel Level 3 Gce Mathematics Advanced - Formulae N Definitions Study Guide Graded A+

y (coding) {Ans: (x - a)/b}x̄ (grouped frequency) {Ans: (Σxf)/(Σf)}Q₂ (discrete) {Ans: (n + 1)/2}Area of histogram bar {Ans: k x frequency}ȳ (coding) {Ans: (x̄ - a)/b}Q₂ (continuous/grouped frequency) {Ans: n/2}Comparing data {Ans: - compare a measure of location - compare a measure of spread Median should not be used with standard deviation and mean should not be used with interquartile range}Q₁ (continuous/grouped frequency) {Ans: n/4}ⁿCᵣ {Ans: n!/(r!(n-r)!)}Q₁ (discrete) {Ans: n/4 - if integer 'a', take mean of the 'a'th data point and 'a+1'th data point - if not integer, round up and take the corresponding data point}Q₃ (discrete) {Ans: 3n/4 - if integer 'a', take mean of the 'a'th data point and 'a+1'th data point - if not integer, round up and take the corresponding data point}Q₃ (continuous/grouped frequency) {Ans: 3n/4}x̄ (quantative data) {Ans: (Σx)/n}Cleaning data {Ans: Removing anomalies (outliers)}σᵧ {Ans: σₓ/b}Frequency density {Ans: frequency / class width}