A real-world culinary business simulation where 6th-grade students design a restaurant event menu, balancing strict budget limits using multi-digit division and fluently calculating decimal costs, sales tax, and per-guest pricing.
Bistro Event Menu Maker • Student Project Portfolio Page 2 of 3
Part 3: Master Invoice & Budget Audit
Calculate total expenses, apply sales tax, and analyze per-guest costs.
Spending Limit
$165.00 Max
Course Item
Packs
Pack Price
Total Line Cost
1. Appetizer: ________________________
______
$________
$________
2. Signature Beverage: __________________
______
$________
$________
3. Main Entree: _______________________
______
$________
$________
4. Side Dish: _________________________
______
$________
$________
5. Dessert: ___________________________
______
$________
$________
Step 1: Subtotal & Sales Tax
Add all 5 items (line up decimal points!), then multiply subtotal by 0.08:
Food Subtotal: $____________
Sales Tax (Subtotal × 0.08): $____________
Grand Total (Subtotal + Tax): $____________
Step 2: Budget Audit & Per-Guest Pricing
Budget Variance ($165.00 − Grand Total):
Status: Under Budget Over Budget (Revise!)
Per-Guest Cost (Multi-Digit Division):
Divide: Grand Total ÷ 24 guests (to nearest cent):
Cost Per Guest: $_____________
Chef's Financial Debrief
1. Explain how you handled division remainders when calculating how many packages to buy. Why would standard rounding rules (rounding down if decimal is under .5) cause a catering disaster?
2. If you wanted to make a $120.00 profit on this 24-person banquet, how much would you need to charge each guest? (Hint: Total Revenue Needed = Grand Total Cost + $120.00; then divide by 24):
Bistro Event Menu Maker • Student Project Portfolio Page 3 of 3
Multiply Subtotal by decimal 0.08:
Tax = $142.50 × 0.08 = $11.40
Grand Total: $142.50 + $11.40 = $153.90
Line up decimals when adding or subtracting! $165.00 - $153.90 = $11.10 Under Budget ✓
The Wholesale Pantry Catalog
Store Menu Overview
Category A & E
Starters & Drinks
• Bruschetta (8 srv / $6.48)
• Phyllo Triangles (6 srv / $7.92)
• Crudité Platter (12 srv / $10.20)
• Citrus Punch (12 srv / $5.40)
• Peach Tea (8 srv / $4.24)
Category B
Main Entrees
• Baked Ziti (12 srv / $21.36)
• Lemon Chicken (6 srv / $17.88)
• BBQ Sliders (8 srv / $19.60)
• Sage Ravioli (8 srv / $22.80)
Category C & D
Sides & Desserts
• Green Beans (8 srv / $5.84)
• Mashed Potatoes (12 srv / $8.76)
• Fudge Brownies (12 srv / $9.48)
• Fruit Tartlets (8 srv / $11.60)
• Cheesecake Bites (6 srv / $8.82)
Compare unit costs carefully before locking in your menu choices High entree cost requires thriftier sides & desserts!
• “When you divide 24 by your item's serving size, what does your remainder represent? Does it mean 2 packages or can someone eat half a box? What happens if you round down?”
During Decimal Cost Operations (6.NS.3):
• “How many decimal places are in your pack price? How does that determine the decimal placement in your product? How is adding decimals in the invoice different from multiplying?”
During Sales Tax & Budget Check:
• “Why do we multiply by 0.08 rather than 0.8 to find an 8% tax? If your Grand Total is $168.20, what specific adjustments can your culinary team make to get under $165.00?”
Proactive Interventions for Common Misconceptions
Common Pitfall
Why Students Stumble
Targeted Teacher Coaching
Standard rounding on remainders (rounding down)
Students apply rote rules: \(24 \div 5 = 4.8 \rightarrow 5\), but \(24 \div 7 = 3.4 \rightarrow 3\).
Ask: “If you buy 3 packs of 7, how many guests get food? (21). Who are the 3 hungry guests?”
Miscalculating 8% Sales Tax as 0.8
Confusing 80% (0.8) with 8% (0.08), generating taxes equal to almost the whole meal!
Remind students that “percent” means per hundred. 8 cents per dollar is 0.08. Check if tax is reasonable ($10–$13).
Aligning decimals during multiplication
Students try to line up whole number packages with decimal places in pack prices.
Review: Multiply as whole numbers first, then count total decimal places in factors to place the point.
Support & Scaffolding (Tier 1/2)
• Divisor Anchor: Encourage items with 6, 8, or 12 servings first, as they divide 24 evenly (\(24 \div 6 = 4\), \(24 \div 8 = 3\), \(24 \div 12 = 2\)).
• Grid Paper: Provide 1/4-inch graph paper to keep decimal columns aligned during subtotal addition.
• Pre-Check: Have students verify item codes and pack counts before calculating dollar amounts.
Extension & Challenge
• Food Waste Metric: Calculate total excess portions across all 5 courses and compute the dollar value of the leftover food.
• Profit Margin Optimization: If the client pays $20.00 per guest ($480 total revenue), calculate net profit: \( \$480 - \text{Grand Total} \).
• Recipe Fraction Scaling (6.NS.1): Calculate what fraction of a package was used vs. leftover (\(24/30 = 4/5\) used, \(1/5\) leftover).
Quotient is 6 with remainder; rounded to nearest hundredth (cent) = $6.47 per person.
Question 1 (Remainder Interpretation):
“In food purchasing, any remainder means guests are left without food unless another package is purchased. Standard mathematical rounding tells us to round down for decimals under .5, but in catering, rounding down leaves real guests hungry. Therefore, we must always round UP to the next whole package.”
Question 2 ($120.00 Profit Calculation):
“First, add profit to total cost: \(\$155.26 + \$120.00 = \$275.26\). Then divide by 24 guests: \(\$275.26 \div 24 \approx \mathbf{\$11.47\text{ per guest}}\) (or add \(\$120 \div 24 = \$5.00\) profit to unit cost: \(\$6.47 + \$5.00 = \$11.47\)).”
Menu Maker Answer Key • Master Teacher Solutions Page 2 of 2
