Find the volume of a rectangular prism
A rectangular prism has a length of 5 cm, a width of 3 cm, and a height of 2 cm. What is its volume?
V = 5 × 3 × 2
V = 30 cm³
Answer: 30 cubic centimeters
A rectangular prism has a length of 6 cm, a width of 4 cm, and a height of 3 cm.
What is the volume?
V = l × w × h
V = 6 × 4 × 3
V = 72 cm³
Answer: 72 cubic centimeters
8+(6−2)
Solution:
First solve inside the parentheses:
7 + 3 = 10
Then:
5 × 10 = 50
Answer: 50
What does the expression 7 + 5 mean?
The expression means the sum of 7 and 5, or 7 increased by 5.
7 + 5 = 12
Answer: The sum of 7 and 5 is 12.
A storage box is 8 inches long, 4 inches wide, and 3 inches tall. What is the volume?
V = 8 × 4 × 3
V = 96 in³
Answer: 96 cubic inches
A cereal box is 10 inches long, 5 inches wide, and 2 inches tall.
What is the volume of the cereal box?
Solution:
V = l × w × h
V = 10 × 5 × 2
V = 100 in³
Answer: 100 cubic inches
5×(7+3)
Solution:
First solve inside the parentheses:
7 + 3 = 10
Then:
5 × 10 = 50
Answer: 50
What does the expression 18 - 6 mean?
Solution:
The expression means the difference between 18 and 6, or 6 taken away from 18.
18 - 6 = 12
Answer: The difference between 18 and 6 is 12.
A rectangular aquarium has a length of 12 feet, a width of 5 feet, and a height of 4 feet. How much space is inside the aquarium?
V = 12 × 5 × 4
V = 240 ft³
Answer: 240 cubic feet
A rectangular swimming pool is 15 meters long, 6 meters wide, and 2 meters deep.
What is the volume of the pool?
Solution:
V = l × w × h
V = 15 × 6 × 2
V = 180 m³
Answer: 180 cubic meters
24÷(4+2)+5
Solution:
First solve inside the parentheses:
4 + 2 = 6
Then divide:
24 ÷ 6 = 4
Then add:
4 + 5 = 9
Answer: 9
Explain the meaning of the expression 4 × (6 + 2).
Solution:
The parentheses tell us to add 6 and 2 first.
6 + 2 = 8
Then multiply 4 by 8:
4 × 8 = 32
Answer: The expression means 4 groups of the sum of 6 and 2. The value is 32.
A rectangular prism has a volume of 360 cubic centimeters. Its length is 10 cm and its width is 6 cm. What is its height?
V = l × w × h
360 = 10 × 6 × h
360 = 60h
h = 360 ÷ 60
h = 6 cm
Answer: 6 centimeters
A rectangular prism has a length of 12.5 feet, a width of 4 feet, and a height of 3 feet.
What is the volume?
Solution:
V = l × w × h
V = 12.5 × 4 × 3
V = 50 × 3
V = 150 ft³
Answer: 150 cubic feet
3[8+(12−5)]
Solution:
Start with the parentheses:
12 - 5 = 7
Then:
8 + 7 = 15
Then multiply:
3 × 15 = 45
Answer: 45
Explain the meaning of the expression 30 ÷ (5 + 1).
Solution:
First find the sum inside the parentheses:
5 + 1 = 6
Then divide 30 by 6:
30 ÷ 6 = 5
Answer: The expression means 30 divided by the sum of 5 and 1. The value is 5.
A shipping box has a length of 15 inches, a width of 8 inches, and a height of 6 inches. The company wants to fill the box with small cubes that each have a volume of 8 cubic inches. How many small cubes can fit inside the box if the entire volume is used?
Step 1: Find the volume of the box.
V = 15 × 8 × 6
V = 720 in³
Step 2: Divide by the volume of each small cube.
720 ÷ 8 = 90
Answer: 90 small cubes
A storage container is shaped like a rectangular prism. It has a length of 18 inches, a width of 7.5 inches, and a height of 4 inches.
What is the volume of the container?
Solution:
V = l × w × h
V = 18 × 7.5 × 4
V = 135 × 4
V = 540 in³
Answer: 540 cubic inches
40−2[6+(15−9)]
Solution:
First solve the innermost parentheses:
15 - 9 = 6
Then:
6 + 6 = 12
Then multiply:
2 × 12 = 24
Finally:
40 - 24 = 16
Answer: 16
A student says that 8 + 3 × 4 means “add 8 and 3, then multiply by 4.” Is the student correct? Explain.
❌ No, the student is not correct.
Multiplication comes before addition.
First:
3 × 4 = 12
Then:
8 + 12 = 20
The expression means 8 plus the product of 3 and 4.
Answer: No. The expression means 8 plus 3 groups of 4, and its value is 20.