Properties of Multiplication — Answer Key
Part A: Fill in the Blank
Write the missing word or number on each line.
1. Grade 3 commutative: 4 x 7 = 7 x 4 so the product stays the same.
Grade 3 commutative property: a x b = b x a.
2. Grade 3: use commutative to rewrite 2 x 9 as 9 x 2 and solve to 18.
Grade 3: 9 x 2 = 18, same as 2 x 9.
3. Grade 3 associative: (2 x 3) x 5 = 2 x (3 x 5) = 30.
Grade 3 associative: (a x b) x c = a x (b x c).
4. Grade 3: to solve 5 x 7 x 2 easily, first do 5 x 2 = 10, then 10 x 7 = 70.
Grade 3: rearranging to 10 x 7 = 70 is faster than 35 x 2.
5. Grade 3: 4 x 3 x 25 = 4 x 25 x 3 = 100 x 3 = 300.
Grade 3 commutative plus associative make 100 x 3 = 300.
6. Grade 3: 6 x 5 x 2 = 6 x (5 x 2) = 6 x 10 = 60.
Grade 3 associative: regroup to get 6 x 10 = 60.
7. Grade 3 commutative: 8 x 3 = 3 x 8 with product 24.
Grade 3: 3 x 8 = 24, same as 8 x 3.
8. Grade 3: (4 x 2) x 6 = 4 x (2 x 6) = 4 x 12 = 48.
Grade 3 associative: 4 x 12 = 48.
9. Grade 3: 7 x 2 x 5 rearranges to 7 x (2 x 5) = 7 x 10 = 70.
Grade 3: commutative plus associative give 7 x 10 = 70.
Part B: Matching
Match each item on the left to the correct answer on the right.
1. Match each item to its correct answer.
Grade 3: 3 x 4 x 5 rearranged as 3 x (4 x 5)
→ 60
60
Grade 3: 6 x 2 x 5 grouped as 6 x (2 x 5)
→ 60 also
60 also
Grade 3: 4 x 25 x 2 grouped as (4 x 25) x 2
→ 200
200
Grade 3: 8 x 5 x 2 grouped as 8 x (5 x 2)
→ 80
80
Grade 3 associative: 3x20=60, 6x10=60, 100x2=200, 8x10=80.