Final answer:
Oliver will need to pay $500 out of pocket in addition to the $1,000 he has already paid towards his deductible.
Step-by-step explanation:
Oliver's medical bill is $3,500. He has a deductible of $2,000, which means he needs to pay that amount out of pocket before his insurance coverage starts. He has already paid $1,000 of his deductible, so he still needs to pay $2,000 - $1,000 = $1,000 to reach his deductible.
After reaching his deductible, Oliver will need to pay 20% coinsurance. This means he is responsible for 20% of the remaining $2,500 ($3,500 - $1,000) medical bill, while his insurance will cover the other 80%.
Therefore, Oliver will need to pay 20% of $2,500, which is 0.20 x $2,500 = $500 out of pocket in addition to the $1,000 he has already paid towards his deductible.