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### Course: Digital SAT Math>Unit 3

Lesson 4: Center, spread, and shape of distributions: foundations

# Center, spread, and shape of distributions — Harder example

Watch Sal work through a harder Center, spread, and shape of distributions problem.

## Want to join the conversation?

• How is this the harder example? This is the easiest one in all of the questions.
• They probably mean it's harder by how the question is worded.
• Bruh basic example was a lot harder than the hard example
• what are center, spread and shape of distributions,?
• Center is exactly what the name implies, it's the middle or average value of a data set. Mean and median are the two best measures of center. You should use mean when there aren't any outliers, extremely high or low values, as mean can be affected by outliers, changing the mean that you get. Median should be used when there aren't any outliers, as median doesn't change by a large amount.

Spread is the size of a data set. Interquartile Range(IQR) and Standard Deviation are the two best measures of center. IQR can be used when there are no outliers and it can be found by subtracting Quartile 3 and Quartile 1, which are two values in a boxplot. Standard Deviation is hard for me to explain but it's easy enough to look up. Sorry about that. You should only use standard deviation if there aren't any outliers.

Hope that helped! :)
• a week left for sat and im still grinding myself here
• looks like SAL by mistake replaced the videos by each other
• Just a heads up to avoid confusion... The 18 he wrote should have been an 8. He accidentally added a 1 and then forgot to take it out
• Yes sjeremiah2003, this is the mistake. It should be 8 instead of 18. We can ignore this mistake.
(1 vote)
• I hope all questions in the sat are like this. I will get a perfect score