1) 405 × 100 = 40500, 405 × 18 = 7290, 40500 + 7290 = 47792) 497 × 38 = 18886, 496 × 38 = 18848, 18886 - 18848 = 33) 344 × 100 = 34400, 344 × 208 = 71472, 34400 + 71472 = 105874) 400 - 2 + 2001 = 2400
1) 405 × 100 = 40500, 405 × 18 = 7290, 40500 + 7290 = 4779
2) 497 × 38 = 18886, 496 × 38 = 18848, 18886 - 18848 = 3
3) 344 × 100 = 34400, 344 × 208 = 71472, 34400 + 71472 = 10587
4) 400 - 2 + 2001 = 2400