Quiz Clean Data and Organize Data

What is the main purpose of cleaning data before analysis?

• To make it look nicer

• To ensure accuracy, consistency, and reliability

• To reduce file size

• To save time typing

Which function in Excel can be used to remove extra spaces from text?

• REMOVE()

• CLEAN()

• TRIM()

• SPACE()

What is a NULL value in a dataset?

• A value equal to zero

• A missing or empty value

• A special character

• A duplicate entry

Why are special characters like “@” or “#” a problem in data analysis?

• They slow down computers

• They confuse visual charts

• They can disrupt data processing and formulas

• They look unprofessional

What Excel tool can be used to eliminate repeated rows of data?

• Merge & Center

• Data Validation

• Remove Duplicates

• Conditional Formatting

Which of the following is a common method for handling missing data?

• Ignoring it completely

• Replacing it with average (Mean), Median or most common values

• Deleting the entire file

• Changing it to zero without explanation

What is “data validation” in Excel used for?

• To calculate averages

• To create charts

• To prevent invalid data entry

• To highlight top values

What kind of inconsistency might you fix under “inconsistent formatting”?

• Missing rows

• Different column names

• Mixed date or number formats

• File extensions

Which formula in Excel counts how many blank cells exist in a range?

• COUNTBLANK()

• COUNT()

• ISNULL()

• ISBLANK()

Why is removing duplicates important in data analysis?

• To save space

• To make the spreadsheet easier to print

• To avoid skewing analysis and metrics

• To follow spreadsheet etiquette