Вправи 301 - 450 » 409-410
409. а) 829 • 103 + 103 • 206 = 103 • (829 + 206) = 103 • 1035 = 103 • (1000 + 35) = 103000 + 3605 = 106605. б) 2436 • 1001 + 2436 = 2436 • (1001 + 1) = 2436 • 1002 = 2440872. 410. а) 536 • 908 – 406 • 908 = 908 • (536 – 406) = 908 • 130 = 118040. б) 1209 • 4003 – 4003 = 4003 • (1209 – 1) = 4003 • 1208 = 4835624.