Challenge No. 165: Based on monthly transactions, categorize each customer for each month into one of the following groups:
New: A customer who has never made a purchase in previous months.
Solved using:Excel (FILTER, HSTACK, IF), Google Sheets, Power Query (Table.Group, List.Difference, List.Distinct), Python, and R.
List.Difference
Returns values that exist in the first list but not in the second in Power Query.
Subjects Taught Exclusively
Challenge No. 85: Column A lists down subjects taught by Female and Male Teachers.
Solved using: SQL.
Determining Missing Fields
Challenge No. 74: Customer information including Name, Family, Phone, and Website is provided in the question table.
Solved using:Excel (ARRAYTOTEXT, FILTER, HSTACK), Power Query (List.Difference, List.Distinct, Text.Combine), Python, and R.
Find Missing Numbers!
Challenge No. 52: In the Question Table, numbers ranging from 1001 to 1018 are listed.
Solved using:DAX, Excel (COUNTIF, FILTER, IF), Power Query (List.Difference), Python, Python in Excel, R, SQL, and VBA.
