Market Rates Worksheet
7th Grade Mathematics • Ratios & Proportional Relationships
Market Rates Worksheet
Name: ___________________
Date: _____________
Period: _________________
Score: _____ / 30
Directions: Calculate unit rates, convert ratios to decimals, and solve multi-step market problems. Show all division work clearly. Round dollar amounts to the nearest cent where necessary.
Part 1 Ratio-to-Decimal Warm-Up
1 pt each • Express ratio as fraction and calculate exact decimal
1. \( 7 : 8 \) Fraction: \(\frac{7}{8}\)
Decimal:
2. \( 9 : 20 \) Fraction: \(\frac{9}{20}\)
Decimal:
3. \( 11 : 4 \) Fraction: \(\frac{11}{4}\)
Decimal:
4. \( 13 : 25 \) Fraction: \(\frac{13}{25}\)
Decimal:
Part 2 Unit Rate Showdown (The Better Buy)
4 pts each • Find unit price to the nearest cent and choose the better buy
5. Honeycrisp Apples: Which grocery stand offers the lower price per pound? Unit Rate = Total Cost ÷ Pounds
Farm Fresh Stand $11.25 for 4.5 lbs
Unit Rate: $ ________ / lb
Orchard Direct Stand $14.10 for 6.0 lbs
Unit Rate: $ ________ / lb
Conclusion: The better buy is ________________________ because it is cheaper by $ ________ per pound.
6. Cold-Pressed Olive Oil: Which bottle has the lowest cost per fluid ounce? Unit Rate = Total Cost ÷ Fl Oz
Bottle A (Verde Gold) $10.25 for 16.4 fl oz
Unit Rate: $ ________ / fl oz
Bottle B (Terra Pure) $15.00 for 25.0 fl oz
Unit Rate: $ ________ / fl oz
Conclusion: The better buy is ________________________ by a savings of $ ________ per fluid ounce.
Part 3 Proportional Rate Table
4 pts total • Determine constant of proportionality and fill missing values
- The Spice Emporium sells organic whole-bean vanilla coffee at a constant proportional rate per pound.
| Weight, \(x\) (pounds) | 2.0 | 3.5 | 5.0 | 8.2 |
|---|
| Total Cost, \(y\) ($) | $29.00 | ________ | $72.50 | ________ |
a. Constant of proportionality (\(k = \frac{y}{x}\)):
\(k =\) $ ________ / lb
b. Proportional Equation:
\(y =\) __________________
Market Rates Worksheet • Part 2: Applications & Mastery
Student Name: ___________________________
Part 4 Gourmet Recipe Scaling
4 pts • Multi-step unit rate application
- The Berry Delight Juice Bar uses a ratio of 3.6 liters of sparkling water for every 8 signature berry mocktails.
Step A: Find the unit rate
How many liters of sparkling water are used per mocktail?
Answer: ________ liters / mocktail
Step B: Scale to a catering event
How many liters are required to prepare 35 mocktails?
Answer: ________ liters
Part 5 Fuel Efficiency & Distance
4 pts • Compare decimal rates and project totals
- Two wholesale delivery vans completed their morning distribution routes:
Van Alpha 133.4 miles on 4.6 gal
Mileage Rate: ________ mpg
Van Beta 158.4 miles on 5.5 gal
Mileage Rate: ________ mpg
On 14 gallons, which van travels further and by how many total miles? Van: _______ by _______ miles
Part 6 Error Analysis: The Cashier's Calculation
3 pts • Critique mathematical reasoning
- A customer purchases 4.8 pounds of fresh cherries for $16.80. An intern cashier calculates: 4.8 ÷ 16.80 = 0.2857... The cashier announces: “The cherries cost approximately $0.29 per pound.”
Explain the cashier's conceptual error:
Calculate the correct unit rate:
Correct Rate: $ ________ / lb
Part 7 Brain Burner Challenge
3 pts • Tiered decimal pricing
- A spice merchant sells saffron at a tiered rate: the first 5.0 grams cost $8.40 per gram. Any additional amount beyond 5.0 grams costs $6.25 per gram. What is the total cost for 8.6 grams of saffron?
Total Cost of 8.6 grams $ _____________
