Explanation:
so, first $300 must be paid without any ifs and whens.
for the rest of the amount the insurance will cover 70%.
the bills total to
700 + 930 = $1630
he must pay $300 of that directly.
that leaves 1630 - 300 = $1330 for the 70/30 split between insurance and patient.
the patient must pay 30% of these $1330.
100% = 1330
1% = 100%/100 = 1330/100 = $13.30
30% = 1% × 30 = 13.30 × 30 = $399
so, the patient pays
300 + 399 = $699
of the $1630 bill.