a)
$$526 – (401 – 294) + 381 =$$
$$= 526 - 107 + 381 =$$
$$= 419 + 381 = 800$$
б)
$$ (694 + 76) – (253 + 472) + 14 = $$
$$= 770 - 725 + 14 =$$
$$= 45 + 14 = 59$$