Grade 4 Multiplication: Unit Review

Worked examples

Real problems from the practice worksheets, solved one step at a time.

1. Example 1

   84 × 78 = ?

   1. Use partial products (area model) method.
   2. Break by place value: 84 = 80 + 4 and 78 = 70 + 8.
   3. 80 × 70 = 5600
   4. 80 × 8 = 640
   5. 4 × 70 = 280
   6. 4 × 8 = 32
   7. Add all partial products: 5600 + 640 + 280 + 32 = 6552

   Answer: 6552

2. Example 2

   73 × 61 = ?

   1. Use partial products (area model) method.
   2. Break by place value: 73 = 70 + 3 and 61 = 60 + 1.
   3. 70 × 60 = 4200
   4. 70 × 1 = 70
   5. 3 × 60 = 180
   6. 3 × 1 = 3
   7. Add all partial products: 4200 + 70 + 180 + 3 = 4453

   Answer: 4453

3. Example 3

   2023 × 6 = ?

   1. Break apart 2023 by place value: 2023 = 2000 + 20 + 3.
   2. 2000 × 6 = 12000
   3. 20 × 6 = 120
   4. 3 × 6 = 18
   5. Add all parts: 12000 + 120 + 18 = 12138

   Answer: 12138