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Statistics and Probability

Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.

Data collection and sampling techniques

Subtopic

Data collection and sampling techniques under Statistics and Probability for Grade 9 IB.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    A researcher wants to ensure both smokers and non-smokers are represented in a health study. They divide the population into these two groups and then pick 5050 from each. This is:

    A.

    Systematic sampling

    B.

    Stratified sampling

    C.

    Convenience sampling

    D.

    Simple random sampling

  2. 2.

    What is a significant disadvantage of conducting a census for a very large population?

    A.

    It is usually free to conduct

    B.

    It is very quick to complete

    C.

    It is often too expensive and time-consuming

    D.

    It only looks at a small portion of the group

  3. 3.

    The speed of a cyclist during a race is an example of:

    A.

    Discrete data

    B.

    Qualitative data

    C.

    Continuous data

    D.

    Secondary data

Download the worksheet for Statistics and Probability - Data collection and sampling techniques to practice offline. It includes additional chapter-level practice questions.

Representation of data: frequency tables, histograms, and cumulative frequency graphs

Subtopic

Representation of data: frequency tables, histograms, and cumulative frequency graphs under Statistics and Probability for Grade 9 IB.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    In a distribution with total frequency NN, the upper quartile is located at which cumulative frequency?

    A.

    0.25N0.25N

    B.

    0.5N0.5N

    C.

    0.75N0.75N

    D.

    NN

  2. 2.

    What is the purpose of a cumulative frequency graph?

    A.

    To show the mode clearly

    B.

    To show how many values are below a certain point

    C.

    To show the mean score

    D.

    To represent categorical data like colors

  3. 3.

    To calculate the mean from a grouped frequency table, we multiply the frequency by the ___ of each class.

    A.

    Upper boundary

    B.

    Lower boundary

    C.

    Midpoint

    D.

    Width

Download the worksheet for Statistics and Probability - Representation of data: frequency tables, histograms, and cumulative frequency graphs to practice offline. It includes additional chapter-level practice questions.

Measures of central tendency for grouped and ungrouped data (mean, median, mode)

Subtopic

Measures of central tendency for grouped and ungrouped data (mean, median, mode) under Statistics and Probability for Grade 9 IB.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    Find the mean of 1010 and 2020.

    A.

    1010

    B.

    1515

    C.

    2020

    D.

    3030

  2. 2.

    If the class intervals are 0−5,5−10,10−150-5, 5-10, 10-15, what is the class width?

    A.

    22

    B.

    55

    C.

    1010

    D.

    1515

  3. 3.

    For the data 8,8,9,10,118, 8, 9, 10, 11, what is the mode?

    A.

    88

    B.

    99

    C.

    1010

    D.

    1111

Download the worksheet for Statistics and Probability - Measures of central tendency for grouped and ungrouped data (mean, median, mode) to practice offline. It includes additional chapter-level practice questions.

Measures of dispersion: range, interquartile range, and box-and-whisker plots

Subtopic

Measures of dispersion: range, interquartile range, and box-and-whisker plots under Statistics and Probability for Grade 9 IB.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    In the data set 5,10,15,20,25,30,355, 10, 15, 20, 25, 30, 35, which value is Q3Q_3?

    A.

    2525

    B.

    3030

    C.

    3535

    D.

    2020

  2. 2.

    In the data set 5,10,15,20,25,30,355, 10, 15, 20, 25, 30, 35, which value is Q1Q_1?

    A.

    55

    B.

    1010

    C.

    1515

    D.

    2020

  3. 3.

    Which visual feature of a box plot shows the range?

    A.

    The width of the box

    B.

    The distance between the two whisker ends

    C.

    The line in the middle of the box

    D.

    The height of the box

Download the worksheet for Statistics and Probability - Measures of dispersion: range, interquartile range, and box-and-whisker plots to practice offline. It includes additional chapter-level practice questions.

Theoretical and experimental probability

Subtopic

Theoretical and experimental probability under Statistics and Probability for Grade 9 IB.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    A number is chosen at random from 11 to 5050. What is the probability that it is a multiple of 1010?

    A.

    110\frac{1}{10}

    B.

    15\frac{1}{5}

    C.

    510\frac{5}{10}

    D.

    150\frac{1}{50}

  2. 2.

    If a letter is chosen at random from the word APPLEAPPLE, what is the probability it is the letter 'P'?

    A.

    15\frac{1}{5}

    B.

    25\frac{2}{5}

    C.

    35\frac{3}{5}

    D.

    45\frac{4}{5}

  3. 3.

    A soccer player takes 5050 penalty shots and scores 4545 goals. What is the experimental probability that the player misses the next shot?

    A.

    0.90.9

    B.

    0.10.1

    C.

    0.050.05

    D.

    0.450.45

Download the worksheet for Statistics and Probability - Theoretical and experimental probability to practice offline. It includes additional chapter-level practice questions.

Probability of combined events using tree diagrams and Venn diagrams

Subtopic

Probability of combined events using tree diagrams and Venn diagrams under Statistics and Probability for Grade 9 IB.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    Two coins are flipped. Use a tree diagram to find the probability of getting two different results (one Head and one Tail).

    A.

    0.25

    B.

    0.50

    C.

    0.75

    D.

    1.00

  2. 2.

    A fair 10-sided die is rolled. What is the probability of rolling a number that is a multiple of 3?

    A.

    0.3

    B.

    0.4

    C.

    0.2

    D.

    0.1

  3. 3.

    In a Venn diagram, n(A∩B)=12n(A \cap B) = 12 and n(A)=30n(A) = 30. Find the number of elements that are in AA but not in BB.

    A.

    18

    B.

    42

    C.

    12

    D.

    30

Download the worksheet for Statistics and Probability - Probability of combined events using tree diagrams and Venn diagrams to practice offline. It includes additional chapter-level practice questions.

Statistics and Probability - Grade 9 Maths (IB) | Krit.club