You're working on a worksheet about the
Associative Property of Multiplication, which states:
> When multiplying three or more numbers, the way you group them (i.e., which two you multiply first) does not change the product.
In symbols:
(a × b) × c = a × (b × c)
Let’s solve each problem step by step.
---
🔢 Problem 1:
5 × 2 × 4
We already know:
5 × 2 × 4 = (5 × 2) × 4 = 10 × 4 = 40
Now we need to fill in:
5 × 2 × 4 = 5 × ___ = ___
This means we’re grouping
2 × 4 first, then multiplying by 5.
So:
→ 2 × 4 =
8
→ 5 × 8 =
40
✔ Fill in:
5 × [8] = [40]
---
🔢 Problem 2:
5 × 2 × 4
Already given:
5 × 2 × 4 = 10 × 4 = 40
Now:
5 × 2 × 4 = 20 × ___ = ___
Wait — how do we get 20? That must be from
5 × 4 = 20, then multiply by 2.
So:
→ 5 × 4 =
20
→ 20 × 2 =
40
✔ Fill in:
20 × [2] = [40]
*(Note: This is still associative — we’re just grouping 5 and 4 together first, then multiplying by 2.)*
---
🔢 Problem 3:
2 × 5 × 6
Given:
2 × 5 × 6 = 2 × 30 = 60 → This comes from (5 × 6) = 30, then 2 × 30.
Now we need:
#### First blank line:
2 × 5 × 6 = 5 × ___ = ___
Group 2 and 6 first:
→ 2 × 6 =
12
→ 5 × 12 =
60
✔ Fill in:
5 × [12] = [60]
#### Second blank line:
2 × 5 × 6 = 6 × ___ = ___
Group 2 and 5 first:
→ 2 × 5 =
10
→ 6 × 10 =
60
✔ Fill in:
6 × [10] = [60]
---
##
✔ Final Answers:
Problem 1:
5 × 2 × 4 = 5 × [8] = [40]
Problem 2:
5 × 2 × 4 = 20 × [2] = [40]
Problem 3:
-
5 × [12] = [60]
-
6 × [10] = [60]
---
## 🧠 Why this works:
The Associative Property lets you regroup multiplication without changing the result. Whether you multiply 5×2 first, or 2×4 first, or 5×4 first — as long as all three numbers are multiplied, the answer is always the same.
This helps simplify mental math! For example, in
2 × 5 × 6, it’s easier to do
2 × 5 = 10, then
10 × 6 = 60 — that’s using the associative property smartly!
Let me know if you’d like a visual diagram or more examples!
Parent Tip: Review the logic above to help your child master the concept of associative property worksheet 3rd grade.