A Collection of Data Science Take-Home Challenges

Query 6


We have a table with users, their country and when they created the account. We want to find:


You can download the data set by clicking here.

head (data,1)

Column Name Value Description
user_id 2 this is id of the user
created_at 2015-02-28 16:00:40 user 2 created her account on Feb, 2 around 4PM
country China She is based in China

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