Grade 12 Maths · Statistics

Predict with the regression line

Use a line of best fit to predict a value, for example estimate a test mark from hours studied, and explain what the gradient means.

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Statistics Grade 12 : line of best fit practiceKevinmathscience
5. Grade 12 Mathematics - Statistics - Exam Question 1JuniorTukkie at the University of Pretoria
Interpreting Slope and Y Intercept of a Regression LIneAmanda Ethridge

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Question 2.4 · May/June 2025 · Paper 2 · National (DBE) · 2 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 online orders on a certain day. The information for these 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
2.4 The supermarket received an online order for items. Predict how long (in minutes) it will take a packer to pack the order and have it ready for delivery.(2)

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  1. 3. Question b · Siyavula Grade 12 Mathematics, 9.2 Curve fitting, Worked example 8 · 1 mark

    The Chemistry and Accounting marks of five learners are given in the table.Diagram for this question
    b For a Chemistry mark of , what mark does the least squares line predict for Accounting?(1)
    Show the memo (1 tick)
    1. ✓
      PredictionUse (on the calculator, then ):
      predicted Accounting mark

      1 mark · Predict with the regression line

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