Nida's way is to draw a grid, split each number into its place values, multiply every box, then add.
a) 78 × 4 = 312
| × | 70 | 8 |
|---|---|---|
| 4 | 280 | 32 |
| Total | 280 + 32 = 312 | |
b) 83 × 9 = 747
| × | 80 | 3 |
|---|---|---|
| 9 | 720 | 27 |
| Total | 720 + 27 = 747 | |
c) 67 × 28 = 1,876
| × | 60 | 7 | Row total |
|---|---|---|---|
| 20 | 1,200 | 140 | 1,340 |
| 8 | 480 | 56 | 536 |
| Total | 1,340 + 536 = 1,876 | ||
d) 53 × 37 = 1,961
| × | 50 | 3 | Row total |
|---|---|---|---|
| 30 | 1,500 | 90 | 1,590 |
| 7 | 350 | 21 | 371 |
| Total | 1,590 + 371 = 1,961 | ||
Step 1. Split each number into its place values (67 → 60 + 7).
Step 2. Write one number across the top and the other down the side.
Step 3. Multiply each pair and write the answer in that box.
Step 4. Add every box.