An invoice dated 5/19/XX received by Jones Supply indicated a balance of $17,000. This balance included a freight charge of $1,000. Terms of the bill were 5/10, 4/30, n/60. Assuming Jones pays off the bill on June 4 he pays:

Lets see how can I sort this out:

We may say that discounts offered are 5% within 10 days, 4% within 30 days and no discount after that. Since bill was paid on June 4 it was over 10 days but under 30 so a discount of 4% will apply to principle balance. In this case total amount paid will be like this: 1000+16000*0.96=16360