Subtracting Zeros & Large Numbers
What is 1,000 − 23?
977
What property is shown? 5 × 1 = 5
Identity Property
Find the missing number: 7 × ___ = 42
6
Add: 326 + 589
915
Expand this number: 345 = ___ + ___ + ___
300 + 40 + 5
Subtract: 40,000 − 5,234
34,766
What property? (2 × 3) × 4 = 2 × (3 × 4)
Associative Property
What number makes this true? 6 + ___ = 13
7
Estimate: 326 + 589 (round to nearest hundred)
300 + 600 = 900
Use expanded form to multiply: 3 × (100 + 20 + 4)
300 + 60 + 12 = 372
What happens when you subtract from a number with lots of zeros? What should you remember?
You must regroup or borrow across multiple zeros. Start from the left until you find a non-zero digit.
What property is shown? 7 × 4 = 4 × 7
Commutative Property
Fill in the blank: ___ × 8 = 64
8
Add using column addition: 45,672 + 23,841
69,513
What’s the distributive property? Give an example.
Distribute multiplication across addition: a(b + c) = ab + ac. Example: 5 × (2 + 3) = 5 × 2 + 5 × 3 = 25
Subtract: 700,000 − 678,912
21,088
Solve using the distributive property: 6 × (10 + 2)
6 × 10 + 6 × 2 = 60 + 12 = 72
What’s the missing element? 5 × ___ = 10 + 15
5 (Because 5 × 2 = 10 and 5 × 3 = 15; 2 + 3 = 5)
Estimate the difference: 82,345 − 41,299
80,000 − 40,000 = 40,000
Use the distributive property to solve: 7 × 103
7 × (100 + 3) = 700 + 21 = 721
900,000 − 387,456
512,544
Solve (3 × 4) × 5 using associative property
12 × 5 = 60 or 3 × 20 = 60.
Write a number sentence that matches this word problem: “I have 3 bags with 4 apples each.”
3 × 4 = 12
Solve and explain using column addition: 786,421 + 193,218
979,639 (stack and add each column)
Multiply using expanded notation: 6 × 432 = ?
6 × (400 + 30 + 2) = 2,400 + 180 + 12 = 2,592