Grade 12 Maths · Statistics

Find the regression line

Use a calculator to find the line of best fit for paired data and write it as y = a + bx, for example y = 3,2 + 1,5x.

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Statistics Grade 12 : line of best fitKevinmathscience

Equation of the least squares regression line using a CASIO scientific calculator Grade 12Login Science

Statistics: Lesson: Linear RegressionMindset

Statistics Grade 12 : line of best fit practiceKevinmathscience

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Question 2.2 · May/June 2025 · Paper 2 · National (DBE) · 3 marks

The manager of a supermarket decided to do a survey on the number of items that a customer ordered online and the time (in minutes) that a packer took to have the order ready for delivery.

The supermarket received

10

online orders on a certain day. The information for these

10

orders is shown below.

Number of items (x): 10, 3, 20, 14, 17, 9, 12, 18, 15, 19
Time (in minutes) (y): 5, 5, 9, 7, 6, 6, 8, 11, 10, 12

2.2 Determine the equation of the least squares regression line.(3)

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More past paper questions: find the regression line

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3. Question a · Siyavula Grade 12 Mathematics, 9.2 Curve fitting, Worked example 8 · 3 marks
The Chemistry and Accounting marks of five learners are given in the table. $Diagram for this question$
a Using a calculator determine the least squares line of best fit for the data set.(3)
Show the memo (3 ticks)Memo
1. ✓
  a $a = - 5, 065 \dots = - 5, 07$ (to two decimal places)
  1 mark · Find the regression line
2. ✓
  b $b = 1, 169 \dots = 1, 17$ (to two decimal places)
  1 mark · Find the regression line
3. ✓
  Equation $\overset{y}{^} = - 5, 07 + 1, 17 x$
  1 mark · Find the regression line
4. Question WE7 · Siyavula Grade 12 Mathematics, 9.2 Curve fitting, Worked example 7 · 3 marks
$Diagram for this question$
WE7 Using a calculator, find the equation of the least squares regression line for the following data:(3)
Show the memo (3 ticks)Memo
1. ✓
  aEnter the five $(x; y)$ pairs in statistics (regression) mode and recall $a$ : $a = 0, 9$
  1 mark · Find the regression line
2. ✓
  bRecall $b$ : $b = 0, 55$
  1 mark · Find the regression line
3. ✓
  Equation $∴ \overset{y}{^} = 0, 9 + 0, 55 x$
  1 mark · Find the regression line
5. Question b · Siyavula Grade 12 Mathematics, 9.3 Correlation, Worked example 9 · 3 marks
A cardiologist wanted to test the relationship between resting heart rate and the peak heart rate during exercise. Heart rate is measured in beats per minute (bpm). The following set of data was generated from $12$ study participants after they had run on a treadmill at $10 km/h$ for $10$ minutes. $Diagram for this question$
b Use your calculator to determine the equation of the line of best fit.(3)
Show the memo (3 ticks)Memo
1. ✓
  a $a = 86, 75$
  1 mark · Find the regression line
2. ✓
  b $b = 0, 96$
  1 mark · Find the regression line
3. ✓
  Equation $y = 86, 75 + 0, 96 x$
  1 mark · Find the regression line

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