1) 25 × 20 × 5 × 7 × 4 = 25 × 20 × 35 × 4 = 500 × 35 × 4 = 17500 × 4 = 70000
2) 42 × 25 + 15 × 42 = 1050 + 630 = 1680
3) (200 - 4) × 15 = 196 × 15 = 2940
1) 25 × 20 × 5 × 7 × 4 = 25 × 20 × 35 × 4 = 500 × 35 × 4 = 17500 × 4 = 70000
2) 42 × 25 + 15 × 42 = 1050 + 630 = 1680
3) (200 - 4) × 15 = 196 × 15 = 2940