LET function for named calculations in Excel - Real Business Scenario

Scenario Mode

👤 Your Role: You are a financial analyst at a retail company.

📋 Request: Your manager wants you to calculate the total profit for each product after applying discounts and costs, using a clear and efficient formula.

📊 Data: You have a table with Product names, Sales Price, Discount %, and Cost per unit.

🎯 Deliverable: Create a new column that uses the LET function to calculate the profit per product, naming intermediate calculations for clarity.

Sample Data

Product	Sales Price	Discount %	Cost
Notebook	20	10	12
Pen	5	5	2
Backpack	50	20	30
Calculator	30	15	18
Ruler	8	0	3
Marker	12	10	6
Folder	15	5	7
Glue	7	0	2

1

Step 1: Insert a new column next to the Cost column and name it 'Profit'.

Expected Result

A new column labeled 'Profit' is ready for formulas.

2

Step 2: In the first cell under 'Profit' (e.g., E2), enter the LET formula to calculate profit by naming the discounted price and profit calculation.

=LET(discountedPrice, B2*(1 - C2/100), profit, discountedPrice - D2, profit)

Expected Result

For Notebook, profit is 6 (20 * 0.9 = 18; 18 - 12 = 6).

3

Step 3: Copy the formula down the 'Profit' column for all products.

Drag the fill handle from E2 down to E9.

Expected Result

Profit values calculated for all products: Pen=2.75, Backpack=10, Calculator=7.5, Ruler=5, Marker=4.8, Folder=7.25, Glue=5.

4

Step 4: Format the 'Profit' column as currency for better readability.

Select the 'Profit' column and apply Currency format.

Expected Result

Profit values display with currency symbol and two decimals.

Final Result

Product    Sales Price  Discount %  Cost  Profit
------------------------------------------------
Notebook   20           10          12    $6.00
Pen        5            5           2     $2.75
Backpack   50           20          30    $10.00
Calculator 30           15          18    $7.50
Ruler      8            0           3     $5.00
Marker     12           10          6     $4.80
Folder     15           5           7     $7.25
Glue       7            0           2     $5.00

✓Using LET makes the formula easier to read by naming intermediate steps.

✓Profit varies by product depending on discount and cost.

✓Backpack has the highest profit of $10.00 after discount and cost.

Bonus Challenge

Modify the LET formula to also calculate and show the profit margin percentage (profit divided by discounted price) in a new column.

Show Hint

Use LET to name discountedPrice and profit, then calculate margin as profit / discountedPrice.

Practice

1. What is the main purpose of the LET function in Excel?

easy

A. To assign names to calculation parts inside a formula for clarity and efficiency

B. To create permanent named ranges in the workbook

C. To automatically sort data in a column

D. To protect cells from editing

Solution

1. Step 1: Understand LET function role

   LET allows naming parts of a formula to make it easier to read and faster to calculate.

2. Step 2: Compare options

   Only To assign names to calculation parts inside a formula for clarity and efficiency correctly describes LET's purpose; others describe unrelated features.

3. Final Answer:

   To assign names to calculation parts inside a formula for clarity and efficiency -> Option A

4. Quick Check:

   LET = Named calculations inside formula [OK]

Hint: LET names parts inside formulas to simplify and speed them [OK]

Common Mistakes:

• Thinking LET creates permanent named ranges
• Confusing LET with sorting or protection features
• Assuming LET works outside formulas

2. Which of the following is the correct syntax to use the LET function in Excel?

easy

A. LET(name1:value1, calculation)

B. LET(name1 = value1, calculation)

C. LET(name1; value1; calculation)

D. LET(name1, value1, calculation)

Solution

1. Step 1: Recall LET syntax

   LET uses commas to separate pairs: name, value, then final calculation.

2. Step 2: Check options

   Only LET(name1, value1, calculation) uses commas and correct order: LET(name1, value1, calculation).

3. Final Answer:

   LET(name1, value1, calculation) -> Option D

4. Quick Check:

   LET syntax uses commas, not equals or semicolons [OK]

Hint: Use commas to separate name, value, and calculation in LET [OK]

Common Mistakes:

• Using equals sign (=) inside LET arguments
• Using semicolons (;) instead of commas
• Using colon (:) instead of comma

3. What is the result of this formula?
=LET(x, 5, y, 3, x * y + 2)

medium

A. 17

B. 25

C. 15

D. 8

Solution

1. Step 1: Assign variables inside LET

   x = 5, y = 3 as defined in the formula.

2. Step 2: Calculate expression

   x * y + 2 = 5 * 3 + 2 = 15 + 2 = 17.

3. Final Answer:

   17 -> Option A

4. Quick Check:

   5*3+2 = 17 [OK]

Hint: Calculate named variables first, then final expression [OK]

Common Mistakes:

• Adding before multiplying (wrong order)
• Using variable names outside LET scope
• Ignoring the +2 at the end

4. Identify the error in this formula:
=LET(x, 10, y, x + 5, x * y)

medium

A. Missing final calculation argument

B. LET cannot use variables inside its own definitions

C. The formula is correct and will return 150

D. Variable names must be single letters only

Solution

1. Step 1: Analyze LET variable usage

   Variable y uses x which is allowed because x is defined before y.

2. Step 2: Calculate final result

   x = 10, y = 10 + 5 = 15, so x * y = 10 * 15 = 150.

3. Final Answer:

   The formula is correct and will return 150 -> Option C

4. Quick Check:

   LET supports sequential variable use = 150 [OK]

Hint: Variables can use earlier variables inside LET [OK]

Common Mistakes:

• Thinking variables can't reference earlier ones
• Assuming missing arguments cause error here
• Believing variable names must be single letters

5. You want to calculate the average of three numbers (in cells A1, A2, A3) and then add 10 to the result using LET. Which formula correctly does this?

hard

A. =LET((A1 + A2 + A3) / 3, avg + 10)

B. =LET(avg, (A1 + A2 + A3) / 3, avg + 10)

C. =LET(avg, A1 + A2 + A3 / 3, avg + 10)

D. =LET(avg, (A1 + A2 + A3) / 3 + 10)

Solution

1. Step 1: Define average correctly

   avg = (A1 + A2 + A3) / 3 calculates the average of three cells.

2. Step 2: Add 10 to average in final calculation

   Use avg + 10 as the last argument to add 10 to the average.

3. Final Answer:

   =LET(avg, (A1 + A2 + A3) / 3, avg + 10) -> Option B

4. Quick Check:

   LET with named average then add 10 = =LET(avg, (A1 + A2 + A3) / 3, avg + 10) [OK]

Hint: Name average first, then add 10 in final LET argument [OK]

Common Mistakes:

• Forgetting parentheses around sum before division
• Missing variable name in LET
• Adding 10 inside variable definition instead of final calculation