GRADE 7 MATHEMATICS (7.3) Patterns, relationships, and algebraic thinking. The student solves problems involving proportional relationships. The student is expected to: (B) estimate and find solutions to application problems involving proportional relationships such as similarity, scaling, unit costs, and related measurement units.
Problem #1: A 30-ounce bottle of salad dressing costs $2.50. What will a 40-ounce bottle of salad dressing cost if the unit cost remains the same? Show your work.
Problem #2: The prices of 3 different size bottles of shampoo are given in the table. Shampoo Prices Bottle Size Unit Price (ounces) Cost 20 $3.50 30
$5.40
36
$7.20
Determine the unit cost per ounce for each size bottle of shampoo. Write the unit cost for each size bottle in the table. Which size cost the least per ounce? __________ Which size cost the most per ounce? _____
1. What mathematical concepts and vocabulary do I need to know to be able to work these problems?
2. Will the Grade 7 Mathematics Formula Chart be helpful on these problems? Why or why not?
3. Would a picture or diagram be helpful on these problems? If so, how?
4. What problem-solving strategy or strategies will I use to help solve these problems?
5. Extension (7.1A): Order the size of shampoos from least cost per ounce to most cost per ounce.
TEKSING TOWARD TAKS © 2006
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GRADE 7 MATHEMATICS (7.3) Patterns, relationships, and algebraic thinking. The student solves problems involving proportional relationships. The student is expected to: (B) estimate and find solutions to application problems involving proportional relationships such as similarity, scaling, unit costs, and related measurement units.
Problem #1: A 30-ounce bottle of salad dressing costs $2.50. What will a 40-ounce bottle of salad dressing cost if the unit cost remains the same? Show your work.
Problem #2: The prices of 3 different size bottles of shampoo are given in the table. Shampoo Prices Bottle Size Unit (ounces) Price Cost 20 $3.50 30
$5.40
36
$7.20
Determine the unit cost per ounce for each size bottle of shampoo. Write the unit cost for each size bottle in the table. Which size cost the least per ounce? __________ Which size cost the most per ounce? _____
TEKSING TOWARD TAKS © 2006
Page 2
GRADE 7 MATHEMATICS (7.3) Patterns, relationships, and algebraic thinking. The student solves problems involving proportional relationships. The student is expected to: (B) estimate and find solutions to application problems involving proportional relationships such as similarity, scaling, unit costs, and related measurement units.
Edison School District is hiring custodial help for $14.00 per hour. If the average custodian works 38 hours a week, what are his weekly earnings before deductions?
Last month Martha worked for a total of 52 hours. She earned $8.25 per hour. Which is the best estimate of the total amount Martha earned last month?
A
$512
A
$480
B
$532
B
$400
C
$522
C
$350
D
$632
D
$300
The following table shows the various prices and sizes of yogurt that can be purchased at the local whole food store. Yogurt Size (in Ounces) 6 8 9 12
Shop Quick Grocery has 211 bags of chips on the display rack. They sell for $0.89 each. What is the best estimate for the value of the chips?
Price
A
$80
$0.54 $0.72 $1.08 $1.32
B
$90
C
$100
D
$200
Which size of yogurt costs the most per ounce? A
The 12-ounce carton only
B
The 8-ounce and 9-ounce cartons
C
The 9-ounce carton only
D
They all cost the same per ounce.
The following table shows the various prices and sizes of snack chips that can be purchased at the local grocery store. Snack Chip Package (in Ounces) 10 14 18 20
Patricia bought 21 loaves of bread for $16.59, including tax. What was the unit cost of a loaf of bread? A
$0.95 per loaf
B
$0.85 per loaf
C
$0.79 per loaf
D
$0.76 per loaf
TEKSING TOWARD TAKS Š 2006
Price $1.30 $1.82 $2.34 $2.60
Which size of snack chips costs the least per ounce? A
The 14-ounce package only
B
The 10-ounce and 14-ounce packages
C
The 20-ounce package only
D
They all cost the same per ounce.
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