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=184092Verify that the mean is 42.6 and the standard deviation is 19.3 for these data.
96 exam-style questions on Edexcel A Level Maths Measures of Location and Spread, covering 2.1 Measures of Central Tendency, 2.2 Other Measures of Location, 2.3 Measures of Spread, 2.4 Variance and Standard Deviation, and 2.5 Coding. Each one has a worked solution and a mark scheme showing where the marks go.