The CO2 _2\,2 emissions, x x\,x g/km, of 20 cars are coded using
y=x−50010\displaystyle y = \frac{x - 500}{10}y=10x−500
For the 20 coded values, the mean is 2.4 and the standard deviation is 0.6.
Find the mean of the CO2 _2\,2 emissions.
Find the standard deviation of the CO2 _2\,2 emissions.
State the effect on the standard deviation of subtracting 500 from every value.
105 exam-style questions on WJEC A Level Maths 2.2 Data presentation and interpretation, covering 2.2.1 Data presentation and interpretation, 2.2.2 Data presentation and interpretation, 2.2.3 Data presentation and interpretation, 2.2.4 Data presentation and interpretation, 2.2.5 Data presentation and interpretation, 2.2.6 Data presentation and interpretation, 2.2.7 Data presentation and interpretation, 2.2.8 Data presentation and interpretation, and 2.2 Data presentation and interpretation. Each one has a worked solution and a mark scheme showing where the marks go.