Removing duplicates in Google Sheets - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the formula to remove duplicates from the range A1:A10.

Google Sheets

=UNIQUE([1])

Drag options to blanks, or click blank then click option'

AA10

BA1

CA1:A10

DA1:A9

Attempts:

3 left

💡 Hint

Common Mistakes

Using a single cell instead of a range.

Selecting a range that does not include all data.

The UNIQUE function removes duplicate values from the specified range. Here, the range A1:A10 is used to get unique values.

2fill in blank

medium

Complete the formula to remove duplicates from columns A and B together (rows 1 to 10).

Google Sheets

=UNIQUE([1])

Drag options to blanks, or click blank then click option'

AA1:B10

BA1:A10

CB1:B10

DA1:B9

Attempts:

3 left

💡 Hint

Common Mistakes

Selecting only one column when duplicates depend on multiple columns.

Using an incomplete range.

To remove duplicates based on multiple columns, provide the range covering those columns. Here, A1:B10 covers columns A and B for rows 1 to 10.

3fill in blank

hard

Fix the error in the formula to remove duplicates from the range C2:C20.

Google Sheets

=UNIQUE([1])

Drag options to blanks, or click blank then click option'

AC2:C20

BC2-C20

CC2;C20

DC2:C2O

Attempts:

3 left

💡 Hint

Common Mistakes

Using a dash '-' instead of a colon ':'.

Using semicolons or misspelled cell references.

The correct range syntax uses a colon ':' between start and end cells. 'C2:C20' is valid, while others cause errors.

4fill in blank

hard

Fill both blanks to remove duplicates from the range D1:E15 and sort the results ascending.

Google Sheets

=SORT(UNIQUE([1]), [2], TRUE)

Drag options to blanks, or click blank then click option'

AD1:E15

B1

C2

DFALSE

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong range or column number.

Confusing TRUE/FALSE for ascending/descending.

The UNIQUE function removes duplicates from D1:E15. SORT then sorts by the first column (1) ascending (TRUE).

5fill in blank

hard

Fill all three blanks to remove duplicates from A2:C20, sort by the second column descending, and display only the first 5 rows.

Google Sheets

=INDEX(SORT(UNIQUE([1]), [2], [3]), SEQUENCE(5))

Drag options to blanks, or click blank then click option'

AA2:C20

B2

CFALSE

DTRUE

Attempts:

3 left

💡 Hint

Common Mistakes

Using TRUE instead of FALSE for descending.

Not limiting rows with INDEX and SEQUENCE.

UNIQUE removes duplicates from A2:C20. SORT sorts by column 2 descending (FALSE). INDEX with SEQUENCE(5) shows the first 5 rows.

Practice

1. What does the UNIQUE(range) function do in Google Sheets?

easy

A. It highlights duplicate values in the range.

B. It sorts the values in the range alphabetically.

C. It counts how many times each value appears in the range.

D. It returns only the unique values from the given range, removing duplicates.

Solution

1. Step 1: Understand the purpose of UNIQUE()

   The UNIQUE() function is designed to filter out repeated values and return only distinct entries from a range.

2. Step 2: Compare options with UNIQUE() behavior

   'It returns only the unique values from the given range, removing duplicates.' correctly describes that UNIQUE() returns unique values by removing duplicates.

3. Final Answer:

   It returns only the unique values from the given range, removing duplicates. -> Option D

4. Quick Check:

   UNIQUE(range) = unique values [OK]

Hint: Remember: UNIQUE() filters duplicates, not sorting or counting [OK]

Common Mistakes:

• Confusing UNIQUE() with SORT()
• Thinking UNIQUE() counts duplicates
• Assuming UNIQUE() highlights duplicates

2. Which of these is the correct syntax to remove duplicates from the range A1:A10 in Google Sheets?

easy

A. FILTER_DUPLICATES(A1:A10)

B. REMOVE_DUPLICATES(A1:A10)

C. UNIQUE(A1:A10)

D. DELETE_DUPLICATES(A1:A10)

Solution

1. Step 1: Identify the correct function name

   Google Sheets uses UNIQUE() to remove duplicates, not any other function names.

2. Step 2: Check the syntax format

   The correct syntax is UNIQUE(range), so UNIQUE(A1:A10) is valid and works as expected.

3. Final Answer:

   UNIQUE(A1:A10) -> Option C

4. Quick Check:

   Correct syntax = UNIQUE(range) [OK]

Hint: Use UNIQUE() exactly, no other function removes duplicates [OK]

Common Mistakes:

• Using non-existent functions like REMOVE_DUPLICATES()
• Adding extra parentheses or commas incorrectly
• Confusing with FILTER() function

3. Given the data in cells A1:A6 as:
1
2
2
3
1
4
What will be the result of =UNIQUE(A1:A6)?

medium

A. [1, 2, 3, 4]

B. [1, 2, 2, 3, 1, 4]

C. [4, 3, 2, 1]

D. [1, 3, 4]

Solution

1. Step 1: List unique values from the data

   The values are 1, 2, 2, 3, 1, 4. Unique values in order of first appearance are 1, 2, 3, 4.

2. Step 2: Understand UNIQUE() output

   UNIQUE() returns these unique values as a vertical array: 1, 2, 3, 4.

3. Final Answer:

   [1, 2, 3, 4] -> Option A

4. Quick Check:

   UNIQUE removes duplicates, keeps first order [OK]

Hint: UNIQUE() keeps first occurrence, removes repeats [OK]

Common Mistakes:

• Expecting sorted output instead of original order
• Including duplicates in the result
• Confusing UNIQUE() with SORT()

4. You wrote =UNIQUE(A1:A5, TRUE, FALSE, TRUE) but get an error. What is wrong?

medium

A. TRUE should be FALSE to remove duplicates.

B. UNIQUE() takes at most three arguments, extra TRUE causes error.

C. The range A1:A5 is invalid for UNIQUE().

D. UNIQUE() requires a second argument to work.

Solution

1. Step 1: Check UNIQUE() function arguments

   UNIQUE() accepts one required argument (range) and up to two optional boolean arguments ([by_column], [exactly_once]). Adding a fourth TRUE is invalid syntax.

2. Step 2: Understand error cause

   Passing more than three arguments causes a formula parse error in Google Sheets.

3. Final Answer:

   UNIQUE() takes at most three arguments, extra TRUE causes error. -> Option B

4. Quick Check:

   UNIQUE(range[, by_col][, exact]) only up to 3 args [OK]

Hint: UNIQUE() takes at most 3 arguments, no extras [OK]

Common Mistakes:

• Adding extra arguments to UNIQUE()
• Thinking TRUE/FALSE controls duplicate removal
• Using invalid ranges

5. You have a table with columns A (Name) and B (City) from rows 1 to 8. Some rows have duplicate Name and City pairs. Which formula removes duplicate rows considering both columns together?

hard

A. UNIQUE(A1:B8)

B. UNIQUE(A1:A8)

C. UNIQUE(B1:B8)

D. UNIQUE(A1:B8, TRUE)

Solution

1. Step 1: Understand removing duplicates by multiple columns

   To remove duplicates based on both Name and City, you must include both columns in the UNIQUE() range.

2. Step 2: Check options for correct range

   UNIQUE(A1:B8) uses UNIQUE(A1:B8), which considers both columns together and removes duplicate rows correctly.

3. Final Answer:

   UNIQUE(A1:B8) -> Option A

4. Quick Check:

   UNIQUE(multi-column range) removes duplicate rows [OK]

Hint: Include all columns in UNIQUE() to remove full-row duplicates [OK]

Common Mistakes:

• Using only one column range to remove multi-column duplicates
• Adding extra arguments to UNIQUE()
• Expecting UNIQUE() to sort automatically