Adam asked every teacher at his school how long it took them to travel to work. Adam's results are summarised in the summary statistics below.
n=84∑x=3581∑x2=184 092 n = 84 \quad \sum x = 3581 \quad \sum x^2 = 184\,092 n=84∑x=3581∑x2=184092Calculate the mean and the standard deviation for these data.
121 exam-style questions on OCR A Level Maths 2.2 Data Presentation and Interpretation, covering 2.2.1 Tables and diagrams for single variable data, 2.2.2 Area in a histogram, 2.2.3 Scatter diagrams and regression lines, 2.2.4 Informal interpretation of correlation, 2.2.5 Correlation and causation, 2.2.6 Measures of average and spread, 2.2.7 Calculations of mean and standard deviation, 2.2.8 Outliers, 2.2.9 Selecting or critiquing data presentation, and 2.2.10 Cleaning data. Each one has a worked solution and a mark scheme showing where the marks go.