Statistics 3 Mock Paper 14 2 1. (a) X ~ N 100, 10 (b) 0.2584 2. (a) 11.09 , There is no evidence of association between type of book and type of cover. 3. (a) 2.68 , There is evidence to reject H 0 and conclude that the special diet is more effective in reducing blood cholesterol. (b) Drop in blood cholesterol levels are normally distributed, C.L. Theorem can be applied, Standard deviations of the populations are 22 and 31. 4. (a) 1.312 , insufficient evidence to reject H 0 therefore Poisson model is suitable. 5. (a) 64 (b) 148 (c) 0.0294 (d) 28 6. (a) Stratified sampling. (b) Uses naturally occurring (Strata) groupings. (c) 12.56 (d) (11.70,13.42) (e) 12 is within confidence interval; so the times spent by these students are in agreement with the suggestion of the member of staff. 7. (a) 0.774 , insufficient evidence of positive correlation. (b) 0.881 (c) Evidence of positive correlation. (d) Because it makes no distributional assumptions about the data or order is more important than mark. Product moment correlation assumes bivariate normality and it is very unlikely that these scores will be distributed this way.