# D1: Sampling and Averages

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• Created by: daniella
• Created on: 25-06-13 21:28

## D1.3: averages and spread

What is the IQR?

the interquatile range is the spread of the 2 middle quarters

How can this be calculated?

UQ- LQ

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## D1.5: Averages and spread for grouped data

What are the columns in a frequancy table?

• the specific range
• frequancy
• midpoint
• midpoint x frequancy

SOME HAVE TALLYS AS WELL

what is the mode on this table?

the biggest number in the frequancy

what is the mean in the table?

the total from the midpoint x frequancy sectoin / frequency

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## D1.5: Averages and spread for grouped data

what is the modal class?

similar to mediun... the range with the highest frequency

how can you figure this out?

the row that has the highest number in the frequancy section

how can you figure out the median?

• figure out the total of the frequancies added together is
• add one to this number
• devide it by 2= x
• count from 1 up... without starting at 0 again and figure out which category x falls into
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