Summarizing by state
Another interesting column is land_area, which shows the land area in square miles. Here, you'll summarize both population and land area by state, with the purpose of finding the density (in people per square miles).
counties_selected <- counties %>%
select(state, county, population, land_area)
Questo esercizio fa parte del corso
Data Manipulation with dplyr
Esercizio pratico interattivo
Prova a risolvere questo esercizio completando il codice di esempio.
counties_selected %>%
# Group by state
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# Find the total area and population
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