Averages from frequency tables (AQA GCSE Statistics): Flashcards
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What is the mean formula for a frequency table?
What is the mean formula for a frequency table?
mean = Σfx / Σf
How do you calculate Σfx in a frequency table?
How do you calculate Σfx in a frequency table?
Sum all values in the fx column.
What does Σf represent in mean calculations?
What does Σf represent in mean calculations?
It is the sum of all frequencies in the data set.
How to calculate the mean of a data set?
How to calculate the mean of a data set?
Add all values and divide by the number of values.
How to calculate the mean from grouped data?
How to calculate the mean from grouped data?
Multiply midpoints by frequencies, then divide by total.
What is the first step to calculate the mean of data?
What is the first step to calculate the mean of data?
Sum all the values in the data set.
Common mistake: Forgetting to multiply by frequency?
Common mistake: Forgetting to multiply by frequency?
Always multiply each x-value by its frequency first.
Why is it important to check fx calculations?
Why is it important to check fx calculations?
Errors in multiplication can lead to wrong mean.
What should you do if Σf isn't given?
What should you do if Σf isn't given?
Calculate it by adding all frequencies.
Does the mean have to be one of the original x-values?
Does the mean have to be one of the original x-values?
No, the mean can be different from original values.