(a) Draw two separate scatter diagrams, each with eight points, to illustrate the relationship between \(x\) and \(y\) in the cases where they have a product moment correlation coefficient equal to
exactly + 1 ,
about \({ } ^ { - } 0.4\).
(b) Explain briefly how the conclusion you would draw from a product moment correlation coefficient of + 0.3 would vary according to the number of pairs of data used in its calculation.
(2 marks)
A histogram was drawn to show the distribution of age in completed years of the participants on an outward-bound course.
There were 32 people aged 30-34 years on the course. The height of the rectangle representing this group was 19.2 cm and it was 1 cm in width.
Given that there were 28 people aged 35-39 years,
(a) find the height of the rectangle representing this group.
Given that the height of the rectangle representing people aged 40-59 years was 2.7 cm ,
(b) find the number of people on the course in this age group.