Multiplying Large Numbers
Solve this on your white board. Show your work or no points!
120 x 3
100 x 3= 300
20 x 3 = 60
Add together to get 360
A school library has a rectangular reading rug with an area of 432 square feet. If the length of the rug is 6 feet, what is the width of the rug? Explain or show your reasoning.
Area = L x W
432= 6 x ?
When you are missing a side, you need to use the inverse operation.
(432 ÷ 6 = 72)
Use partial quotient division to solve:
384 ÷ 6
• 6 × 50 = 300 → remainder 84
• 6 × 14 = 84 → remainder 0
Quotient: 50 + 14 = 64
What is the answer to a division problem called?
Write the word on your white board (spelling doesn't matter)
Quotient
What is the formula for finding AREA?
Area = Length x Width
Or
A= L x W
Solve on your white board. Show your work or no points!
150 x 20
15 x 2 = 30. then add two zeros:
3,000
A school playground has a rectangular running area with a total area of 1,824 square feet. If the length of the running area is 24 feet, what is the width of the area? Show all your work.
Area = L x W
1824 = 24 x ?
Missing a side length. means using the inverse operation to solve:
1,824 ÷ 24 = 76
Use partial quotient division to solve:
672 ÷ 8
• 8 × 80 = 640 → remainder 32
• 8 × 4 = 32 → remainder 0
Quotient: 80 + 4 = 84
What is a synonym for "inverse"?
A synonym is a word that means the same thing.
Opposite
What is the formula for finding volume?
Solve this on your white board. Show your work or no points!
450 x 30
400 x 30= 12000
50 x 30= 1500
Add together to get:
13,500
A school art room has a rectangular mural space with an area of 1,152 square feet. If the length of the mural space is 32 feet, what is the width of the space? Explain or show your reasoning.
A = L x W
1152 = 32 x ?
Missing a side length means you need to divide!
1152 divided by 32 is 36
The width is 36 feet.
Use partial quotient division to solve:
1,008 ÷ 12
• 12 × 80 = 960 → remainder 48
• 12 × 4 = 48 → remainder 0
Quotient: 80 + 4 = 84
What is the inverse operation of Multiplication?
Division!
If you are given volume, but are missing the width, what can you do to find the width?
You need to multiply the length and the height and then divide the volume by that product.
Solve this on your white board. Show your work or no points!
1234 x 56
1000 x 50 = 50000
200 x 50 =10000
30 x 50 =1500
4 x 50 = 200
1000 x 6 = 6000
200 x 6 =1200
30 x 6 = 180
4 x 6 = 24
add all together to get 69,104
A community skate park has a rectangular practice area with a total area of 4,560 square feet. If the length of the practice area is 76 feet, what is the width of the practice area? Show all your work for points.
Use the formula for area and plug in your numbers.
A = L x W
4560 = 76 x ?
Since you are missing a side length, you need to use the inverse operation, or opposite operation to solve. The opposite of multiplcation is division:
4,560 divided by 76 is 60
The width is 60 feet.
Use partial quotient division to solve:
1,764 ÷ 14
• 14 × 100 = 1,400 → remainder 364
• 14 × 20 = 280 → remainder 84
• 14 × 6 = 84 → remainder 0
Quotient: 100 + 20 + 6 = 126
What is the second number in a division sentence called? Spelling does not matter.
For instance, the 24 in this example:
3,456 ÷ 24
Divisor!
The equation 64 × 35 = 2,240 is true. Select all true equations (you will choose more than one).
A • 2,240 ÷ 35 = 64
B • 35 × 64 = 2,240
C • 2,240 ÷ 64 = 35
D • 64 ÷ 35 = 2,240
E • 2,240 × 35 = 64
True equations:
• ✅ 2,240 ÷ 35 = 64
• ✅ 35 × 64 = 2,240
• ✅ 2,240 ÷ 64 = 35
Not true:
• ❌ 64 ÷ 35 = 2,240
• ❌ 2,240 × 35 = 64
Solve this on your white board. Show you work or no points!
54,850 x 12 = x
50,000 X 10 = 500,000
4,000 x 10 =40,000
800 x 10 =8,000
50 x 10 = 500
50,000 X 2 = 100,000
4,000 x 2 =8,000
800 x 2 = 1,600
50 x 2 = 100
Add all together to get 658,200
A rectangular storage bin has a base area of 900 square centimeters. The bin is 30 centimeters tall and 20 centimeters wide.
How long is the bin?
Then find the volume of the bin in cubic centimeters.
Area = L x W
900 x ? x 20
Use division to solve for length! 900 ÷ 20 = 45 cm
Volume = L x W x H
OR
Volume = Area of Base x H
900 × 30 = 27,000 cm³
Use partial quotient division to solve:
3,456 ÷ 24
• 24 × 100 = 2,400 → remainder 1,056
• 24 × 40 = 960 → remainder 96
• 24 × 4 = 96 → remainder 0
Quotient: 100 + 40 + 4 = 144
What is the first number in a division sentence called? Again, spelling doesn't matter.
For instance, the 3,456 in this example:
3,456 ÷ 24
Dividend
A rectangular aquarium has a volume of 2,160 cubic centimeters. Its length is 30 cm and its height is 12 cm. What is the width of the aquarium? Show your work.
Volume = length × width × height →
2,160 = 30 x ? x 6
2,160 ÷ (30 × 12)
30 x 12 = 360
2,160 ÷ 360 = 6 cm
The width of the aquarium is 6 cm.