1) 67812 - (489*105 + 7445) 2) (94554:927+884)-109 3) 39405:555+301*203 4) 346252:428-18231:309

67812 – (489 * 105 + 7445) = 9022 489 * 105 = 51345 51345 + 7445 = 58790 67812 - 58790 = 9022 (94554 / 927 + 884) – 109 = 877 94554 / 927 = 102 102 + 884 = 986 986 - 109 = 877 39405 / 555 + 301*203 = 61174 39405 / 555 = 71 301 * 203 = 61103 71 + 61103 = 61174 346252 / 428 – 18231 / 309 = 750 346252 / 428 = 809 18231 / 309 = 59 809 - 59 = 750