Assess Yourself
How well do you understand the ideas in this lesson?
Goal:
Goal:
Show What You Know!
Are you ready to take this lesson's quiz? These questions will help you find out. Go back to the lesson if you do not know an answer.
What is the total cost of the area below if the unit cost is $2?
A grid of 5 rows and 10 columns grid.
- $100
- $50
- 30
- 15
This is correct! 10 units \({\times}\) 5 units \({=}\) 50 square units \({\times}\) $2 \({=}\) $100.
This is incorrect. 10 \({\times}\) 5 \({=}\) 50 \({\times}\) $2 \({=}\) $100.
This is incorrect. Use the distributive property if you need to. \({5 \times (5 + 5) = (5 \times 5) + (5 \times 5) = 25 + 25 = 50}\).
This is incorrect. Find the area and then multiply area by the unit cost.
Alex is ordering a banner for a fundraiser that costs $7 per square foot. If the banner is 2 feet by 20 feet, what is the total cost?
- $280
- $40
- $200
- $140
Great job! 2 ft \({\times}\) 20 ft = 40 ft\({^2}\) \({\times}\) $7 = $280.
This is incorrect. Remember to multiply the area by the unit cost to find the total cost.
This is incorrect. 2 \({\times}\) 20 \({=}\) 40. Multiply 40 by the unit cost.
This is incorrect. Remember to find the area first and then multiply by the unit cost.
Which answer matches the image to solve for the total cost?
- A \({=}\) 7 units \({\times}\) 6 units \({=}\) 42 square units; 42 square units \({\times}\) $6 per square unit \({=}\) $252
- A \({=}\) 7 units \({\times}\) 6 units \({\times}\) 6 units \({=}\) 252 square units
- A \({=}\) 7 units \({\times}\) 6 units \({=}\) 48 square units; 48 square units \({\times}\) $6 per square unit \({=}\) $288
- A \({=}\) 7 units \({\times}\) 6 units \({=}\) 42 units; 42 \({\times}\) $6 per square unit \({=}\) $222
This is correct! Finding the area and then multiplying by the unit cost is how you find the total cost.
This is incorrect. Multiply the area by the unit cost to find the total cost in dollars.
Try again. Check your area calculations.
Try again. Area is given in square units, not units. Check your total cost calculations.
Clara is making glitter bookmarks for her friends. If each bookmark uses a piece of paper that is 2 inches by 6 inches and glitter is 5 cents per square inch, how much will each bookmark cost?
- 60 cents
- $60
- $6
- 30 cents
That is correct! 2 in. \({\times}\) 6 in. \({=}\) 12 in\({^2}\) \({\times}\) 5 cents \({=}\) 60 cents.
Try again. Remember that each square inch is only 5 cents.
Try again. Remember that each square inch is only 5 cents.
Try again. Remember to multiply width times length to find the area. Then multiply area by the unit cost to find the answer.
In which line did the first mistake occur?
An area with a length of 8 and a width of 5. The cost is 3 dollars per square unit. Line 1: A equals 8 units times 5 units Line 2: A equals 40 square units Line 3: 40 square units times 3 dollars per square unit. Line 4: Total Cost equals 140 dollars.
- Line 1
- Line 2
- Line 3
- Line 4
This is incorrect. These are the correct values based on the formula area \({= l \times w}\)
This is incorrect. This is the correct area of the rectangle.
This is incorrect. This is the correct way to find the total cost of the area.
This is correct! This is not the product of 40 square units \({\times}\) $3 per square unit.
Find the total cost.
An area with a length of 8 and a width of 5. The cost is 3 dollars per square unit.
- $120
- $140
- $160
- $40
That is correct. 5 units \({\times}\) 8 units \({=}\) 40 square units \({\times}\) $3 per square unit \({=}\) $120.
Try again. Remember to find the area first and then multiply by the unit cost. Remember the rule when multiplying by a multiple of 10.
Try again. Remember to calculate the area first and then multiply by the unit cost.
Try again. Remember to multiply the area by the unit cost.
Joseph is buying ribbon to place on a present. He needs a piece that is 1 inch by 15 inches. Ribbon costs $5 per square inch. How much will it cost to purchase the ribbon?
- $80
- $75
- $72
- $100
Try again. \({1 \times 15 = 15 \times $5 = $75}\).
This is correct! 1 inch \({\times}\) 15 inches \({=}\) 15 square inches \({\times}\) $5 per square inch \({=}\) $75.
Try again. Check your calculations.
Try again. Check your calculations.
Find the total cost.
An area of 4 rows and 6 columns. The cost is 2 dollars per square unit.
- area \({=}\) 10 square units; total cost \({=}\) $20
- area \({=}\) 24 square units; total cost \({=}\) $24
- area \({=}\) 24 square units; total cost \({=}\) $48
- area \({=}\) 20 square units; total cost $40
This is incorrect. Remember to multiply length times width to find the area.
This is incorrect. Remember to multiply the area by the unit cost to find the total cost.
This is correct! 4 units \({\times}\) 6 units \({=}\) 24 square units \({\times}\) $2 per square unit \({=}\) $48.
This is incorrect. This shape is 4 units by 6 units.
Joseph is going to lay cement in his front yard. If the area of the cement pad is 100 yd\({^2}\) and it costs $9 per square yard, how much will the cement pad cost?
- $900
- $90
- $100
- $109
That is correct! 100 yd\({^2}\) \({\times}\) $9 per square yard \({=}\) $900.
This is incorrect. Remember to multiply 9 times 1 and then add the two zeros from 100 yd\({^2}\).
That is incorrect. Remember, when you multiply a number by a multiple of 100, place zeros from the hundred after the number.
This is incorrect. Remember to multiply the area by the unit cost.
Find the cost.
An area with a length of 3 and a width of 2. The cost is 8 dollars per square unit.
- $48
- $14
- $40
- $26
This is correct! 2 units \({\times}\) 3 units \({=}\) 6 square units \({\times}\) $8 per square unit \({=}\) $48.
This is incorrect. Remember, you need to multiply area and unit cost to find the total cost.
This is incorrect. Remember to multiply length times width to find area.
This is incorrect. Remember to multiply length times width to find area. Then multiply by the unit cost.
Summary
Questions answered correctly:
Questions answered incorrectly: