Statistics test

• What is the formula to calculate the mean?

  Mean = ΣX / n
• What does the mode represent in a data set?

  The mode is the value that appears most frequently in an ordered list.
• How is the median defined in a data set?

  The median is the middle value in an ordered list of numbers.
• What is the formula for calculating the range of a data set?

  Range = H - L
• What does ΣX represent in statistics?

  ΣX represents the sum of all data values.
• What is a frequency table used for?

  A frequency table is used to organize data and find the mean, mode, and median easily.
• What are quartiles in statistics?

  • Quartiles split data into four equal sections.
  • Lower quartile (Q1), median (Q2), and upper quartile (Q3).
  • Q1 is the median of the lower half, Q3 is the median of the upper half.
• What does S.I.Q.R stand for in statistics?


  1. I.Q.R stands for Semi-Interquartile Range.
• How is the S.I.Q.R calculated?

  1. I.Q.R = (Q3 - Q1) / 2
• What does a larger S.I.Q.R indicate about the data?

  A larger S.I.Q.R indicates that the data is more widely spread.
• What are boxplots used for in statistics?

  • Boxplots show the spread within a data set.
  • They allow comparison between two different sets of data.
  • Composite boxplots can display multiple data sets on the same axis.
• What is the formula for standard deviation?

  Standard deviation (SD) = √(Σ(x - X̄)² / N-1)
• What does a smaller standard deviation indicate about a data set?

  A smaller standard deviation indicates that the data points are closer to the mean.
• What is a scatter graph used for?

  • A scatter graph compares two sets of data.
  • It helps visualize the correlation between the data sets.
  • Coordinates are plotted as (x, y).
• What does positive correlation indicate in a scatter graph?

  Positive correlation indicates that as one variable increases, the other variable also increases.
• What does negative correlation indicate in a scatter graph?

  Negative correlation indicates that as one variable increases, the other variable decreases.
• What is the line of best fit in a scatter graph?

  The line of best fit is a straight line that best represents the data points on the graph.
• How do you find the gradient (m) of the line of best fit?

  Gradient (m) = Δy / Δx
• What is the general equation of a straight line?

  The general equation of a straight line is y = mx + c.
• How can you check if your line of best fit is correct?

  You can check by substituting coordinates into the equation and verifying the results.
• How do you find the y-intercept (c) from a graph?

  The y-intercept (c) is found by looking at where the line crosses the y-axis.
• How do you substitute values into the equation of a line?

  You substitute the values of m and c into the equation y = mx + c.