The masses, m m\,m grams, of 40 items are coded using x=m−502x=\dfrac{m-50}{2}x=2m−50. The coded data have mean 3.5 and variance 4.84.
Find the mean mass.
Find the variance of the masses.
Interpret the standard deviation of the masses.
278 exam-style questions on CCEA A Level Maths 2.5 Data presentation and interpretation, covering 2.5.1 Data presentation and interpretation, 2.5.2 Data presentation and interpretation, 2.5.3 Data presentation and interpretation, 2.5.4 Data presentation and interpretation, 2.5.5 Data presentation and interpretation, 2.5.6 Data presentation and interpretation, 2.5.7 Data presentation and interpretation, 2.5.8 Data presentation and interpretation, 2.5.9 Data presentation and interpretation, and 2.5 Data presentation and interpretation. Each one has a worked solution and a mark scheme showing where the marks go.