2013 TJC P2 Q11
2013 TJC P2 Q11
9 marks
Prelims
- May travels regularly from home to the hospital for treatment. She leaves home at \(x\) minutes after 8 am and takes \(y\) minutes to arrive at the hospital. Ten pairs of data are recorded in the table below.
\(x\) \(0\) \(5\) \(10\) \(15\) \(20\) \(25\) \(30\) \(35\) \(40\) \(45\) \(y\) \(31\) \(42\) \(33\) \(48\) \(47\) \(53\) \(68\) \(65\) \(71\) \(70\) - Draw a scatter diagram to illustrate the data, labelling the axes clearly.[1]
- Calculate the equation of the least squares regression line of \(y\) on \(x\) and the value of the linear product moment correlation coefficient for the data.[3]
- Interpret the regression coefficient in the context of the question.[1]
- Draw the regression line of \(y\) on \(x\) on the scatter diagram.[1]
- May has a hospital treatment appointment at 8.45 am on a particular day. If she leaves home at 8.10 am, explain whether she is likely to be on time for her hospital treatment. Comment on the reliability of your answer.[3]
Video Solution:
Video solution locked
A free account saves your progress; this video needs tuition enrolment.
Solution:
Solution locked
680+ questions here come with free worked solutions. A free account saves your questions and progress; this one needs tuition enrolment.
Create a free account to practise similar questions.
Answer:(b)(i) Scatter diagram plotted (ii) \(y=0.945x+31.5\), \(r=0.949\) (iii) Each 1-minute later departure predicts about \(0.945\) minutes more travelling time (iv) Regression line shown (v) Estimated arrival 8.51 am; likely late. The estimate is reasonably reliable because it is interpolation and the linear correlation is strong.
Need help? Join our JC Math tuition classes.
Learn more