Answer: $15,000
Explanation: The 80% coinsurance clause on the property means that the insurance policy holder is agreeing to contribute up to 80% of the property's worth. Hence in the event of a loss to the building worth $20,000; the insures policyholder would receive :
(Actual contribution/expected contribution) x value of loss to the property
Where : Expected contribution = 80% of property's worth
ie (80/100) x $400,000 = $320,000
then the insured is to receive: ($240,000/$320,000) x $20,000 = $15,000