Formula-based rules in Excel - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a formula-based rule in Excel conditional formatting?

A formula-based rule uses a custom formula to decide which cells to format. If the formula returns TRUE for a cell, the formatting is applied to that cell.

beginner

How do you write a formula-based rule to highlight cells greater than 100 in column A?

Use the formula =A1>100 in the conditional formatting rule. This checks if each cell in column A is greater than 100.

intermediate

Why use absolute references (like $A$1) carefully in formula-based rules?

Absolute references fix the cell position when applying the rule to other cells. Using them incorrectly can cause the rule to always check the same cell instead of each cell individually.

beginner

What does the formula =ISBLANK(B2) do in a formula-based rule?

It checks if cell B2 is empty. If B2 is blank, the formula returns TRUE and the formatting is applied.

intermediate

How can you highlight rows where the value in column C is "Done" using a formula-based rule?

Use the formula =$C1="Done" in the conditional formatting rule applied to the whole row range. The $ before C locks the column, so the rule checks column C for each row.

What does a formula-based rule in Excel conditional formatting return to apply formatting?

A FALSE

B A number

C TRUE

D A text string

The formula must return TRUE for the formatting to be applied to the cell.

Which formula highlights cells in column A that are less than 50?

A =A1>50

B =$A1>50

C =A$1<50

D =A1<50

The formula =A1<50 checks if each cell in column A is less than 50.

What happens if you use an absolute reference like $A$1 in a formula-based rule applied to many cells?

A The rule checks the same cell $A$1 for all cells

B The rule adjusts the reference for each cell

C The rule ignores the formula

D The rule applies formatting randomly

Absolute references fix the cell, so the formula always checks $A$1 regardless of the cell being formatted.

Which formula highlights cells that are empty?

A =ISBLANK(A1)

B =A1=0

C =A1>0

D =NOT(ISBLANK(A1))

ISBLANK returns TRUE if the cell is empty, so the formatting applies to blank cells.

To highlight entire rows where column B equals "Yes", which formula is correct?

A =B$1="Yes"

B =$B1="Yes"

C =B1="Yes"

D =$B$1="Yes"

Using $B locks the column B, and the row number adjusts for each row, so the rule checks column B for each row.

Explain how to create a formula-based conditional formatting rule to highlight cells with values above a certain number.

Think about how to write a formula that checks if a cell's value is greater than your number.

Describe the role of absolute and relative references in formula-based conditional formatting rules.

Consider how $ signs affect the formula when applied to many cells.

Practice

1. What does a formula-based rule in Excel do when the formula returns TRUE?

easy

A. It changes the cell's appearance based on the rule.

B. It deletes the cell content.

C. It copies the cell to another sheet.

D. It locks the cell from editing.

Solution

1. Step 1: Understand formula-based rules

   Formula-based rules use formulas that return TRUE or FALSE to decide if formatting applies.

2. Step 2: Effect of TRUE result

   If the formula returns TRUE, Excel applies the formatting like color or font change to the cell.

3. Final Answer:

   It changes the cell's appearance based on the rule. -> Option A

4. Quick Check:

   TRUE formula triggers formatting [OK]

Hint: TRUE formulas trigger formatting changes in cells [OK]

Common Mistakes:

• Thinking the rule deletes or moves data
• Confusing formatting with locking cells
• Assuming FALSE triggers formatting

2. Which of these is the correct formula to highlight cells greater than 50 in conditional formatting?

easy

A. IF(A1>50)

B. A1>50

C. =A1>50

D. =IF(A1>50)

Solution

1. Step 1: Check formula syntax for conditional formatting

   Conditional formatting formulas must start with '=' and return TRUE or FALSE.

2. Step 2: Validate each option

   =A1>50 uses correct syntax and returns TRUE or FALSE directly. IF(A1>50) and A1>50 miss '='. =IF(A1>50) uses incomplete IF without value_if_true and value_if_false.

3. Final Answer:

   =A1>50 -> Option C

4. Quick Check:

   Formula must start with '=' and return TRUE/FALSE [OK]

Hint: Always start formulas with '=' in conditional formatting [OK]

Common Mistakes:

• Omitting '=' at the start
• Using incomplete IF statements
• Writing formulas that don't return TRUE/FALSE

3. Given the formula-based rule with formula =AND(A1>10, A1<20), which cells will be formatted?

medium

A. All cells regardless of value

B. Cells with values equal to 10 or 20

C. Cells with values less than 10 or greater than 20

D. Cells with values between 10 and 20, excluding 10 and 20

Solution

1. Step 1: Understand the AND formula conditions

   The formula checks if A1 is greater than 10 AND less than 20 simultaneously.

2. Step 2: Determine which values satisfy both conditions

   Only values strictly between 10 and 20 (not including 10 or 20) make the formula TRUE.

3. Final Answer:

   Cells with values between 10 and 20, excluding 10 and 20 -> Option D

4. Quick Check:

   AND(A1>10, A1<20) means 10 < A1 < 20 [OK]

Hint: AND means all conditions must be TRUE simultaneously [OK]

Common Mistakes:

• Including boundary values 10 or 20
• Confusing AND with OR logic
• Thinking it formats all cells

4. You wrote the formula =A1>100 for conditional formatting but no cells are highlighted even though some values are above 100. What is the likely problem?

medium

A. The formula is missing the '=' sign at the start.

B. The formula is correct but the range is not set properly.

C. The formula should use IF(A1>100) instead.

D. Conditional formatting does not support comparison operators.

Solution

1. Step 1: Check formula correctness

   The formula '=A1>100' is correct syntax for conditional formatting.

2. Step 2: Consider the formatting range

   If no cells highlight, likely the conditional formatting rule is applied to the wrong or empty range.

3. Final Answer:

   The formula is correct but the range is not set properly. -> Option B

4. Quick Check:

   Correct formula + wrong range = no formatting [OK]

Hint: Check the range where the rule is applied [OK]

Common Mistakes:

• Removing '=' sign
• Using IF unnecessarily
• Believing conditional formatting can't compare values

5. You want to highlight cells in column A that are either blank or contain a number less than 50. Which formula-based rule should you use?

hard

A. =OR(ISBLANK(A1), A1<50)

B. =AND(ISBLANK(A1), A1<50)

C. =IF(A1="", TRUE, A1<50)

D. =NOT(ISBLANK(A1))

Solution

1. Step 1: Understand the condition requirements

   We want to format cells that are blank OR have a number less than 50.

2. Step 2: Choose the correct logical formula

   OR(ISBLANK(A1), A1<50) returns TRUE if either condition is met, matching the requirement.

3. Final Answer:

   =OR(ISBLANK(A1), A1<50) -> Option A

4. Quick Check:

   Use OR for either condition TRUE [OK]

Hint: Use OR to combine multiple conditions [OK]

Common Mistakes:

• Using AND instead of OR
• Misusing IF inside conditional formatting
• Ignoring blank cells condition