Grade 10 Maths · Statistics

Describe skewness and outliers

Say whether data is symmetric, skewed left or skewed right, and spot outliers, for example when the mean is much bigger than the median.

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6. Grade 11 Mathematics - Statistics - Skewed DataJuniorTukkie at the University of Pretoria

Maths Tutorial: Describing Skewness of Boxplots (statistics)Further Maths

Skewness - Right, Left & Symmetric Distribution - Mean, Median, & Mode With Boxplots - StatisticsThe Organic Chemistry Tutor

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Question c · Siyavula Grade 12 Mathematics, 9.1 Revision, Worked example 3 · 3 marks

Three Matric classes wrote a Mathematics test. The test is out of

40

marks and each class has

21

learners. The results of the test are shown in the table below: $Diagram for this question$

c Comparing the mean and median values for each class, comment on the distribution of the test marks for each class.(3)

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More past paper questions: describe skewness and outliers

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3. Question 1.4.1 · November 2024 · Paper 2 · Provincial · 1 mark
The traffic department set up a roadblock on the N12 between Potchefstroom and Klerksdorp. During the first hour, they stopped 11 minibus taxis.
The following dataset is a summary of the number of passengers per minibus taxi.

18, 26, 25, 18, 16, 12, 10, 8, 18, 17, 8
1.4 During the second hour of the roadblock, a further 5 minibus taxis were stopped. The number of passengers in these 5 taxis are: $x$ , 13, 18, $y$ , 20.

These 5 numbers are already arranged from smallest to largest.

The entire dataset for the first and second hours is collectively represented on a box-and-whisker diagram. The new average number of passengers for the 16 taxis is 16. The five-number summary can be seen on the diagram below.

Answer the questions that follow. $Diagram for question 1.4$
1.4.1 Discuss the skewness of the data.(1)
Show the memo (1 tick)Memo
1. ✓
  AnswerSkewed to the left. $\overset{x}{ˉ} < Q_{2}$
  1 mark · Describe skewness and outliers
4. Question 1.4 · November 2024 · Paper 2 · Provincial · 1 mark
Mr Baloyi conducted a survey on the amount of airtime (in Rands) EACH learner had on his or her cellphone.
The data is: 12, 16, 30, 26, 20, 22, 32, 38, 40, 46, 54, 60, 68.
1.4 Comment on the skewness of the data.(1)
Show the memo (1 tick)Memo
1. ✓
  Identify skewnessThe data is skewed to the right (positively skewed).
  1 mark · Describe skewness and outliers
5. Question 1.2 · November 2024 · Paper 2 · Provincial · 1 mark
After utilising GeoGebra to teach geometry, the 14 participants marks out of 100 are displayed in the table below. $Diagram for this question$
1.2 Identify any outlier.(1)
Show the memo (1 tick)Memo
1. ✓
  OutlierOutlier $= 99$
  1 mark · Describe skewness and outliers

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