SPM.2.SL.TZ0.5

pestleMathematicsAASLPaper 2SPM· sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-xsource ↗

The following table below shows the marks scored by seven students on two different mathematics tests.

Let L₁ be the regression line of x on y. The equation of the line L₁ can be written in the form x = ay + b.

Find the value of a and the value of b.

[2]

Let L₂ be the regression line of y on x. The lines L₁ and L₂ pass through the same point with coordinates (p , q).

Find the value of p and the value of q.

[3]

Markscheme / solution

a = 1.29 and b = −10.4 A1A1

[2 marks]

recognising both lines pass through the mean point (M1)

p = 28.7, q = 30.3 A2

[3 marks]

Examiners’ report

[N/A]