Tính bằng cách thuận tiện. a) 3 829 × 2 × 5 = ………………………………… b) 5 × 2 × 30 293 = ……………………………….. c) 2 × 326 × 5 = …………………………………… d) 5 × 92 × 2 = ……………………………………..

a) 3 829 × 2 × 5 = 3 892 × (2 × 5) = 3 892 × 10 = 38 290

b) 5 × 2 × 30 293 = (5 × 2) × 30 293 = 10 × 30 293 = 302 930

c) 2 × 326 × 5 = (2 × 5) × 326 = 10 × 326 = 3 260

d) 5 × 92 × 2 = (5 × 2) × 92 = 10 × 92 = 920