Use an online calculator to do a "time value of money" calculation that shows him how much debt you can run up when you're using a credit card that charges 17% interest.

用在线计算器做一个“金钱的时间成本”的计算，然后告诉他当他用一张利息17%的信用卡时会有多少债务滚滚而来。

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Assume that the Gross Profit is based on the calculation of (the investment return of the account balance) - (the interest paid).

假定净利润基于(投资收益)-(所付利息)的计算。

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The gang's motives, however, and perhaps Lord Mandelson's especially, were more complex than a simple calculation of personal self-interest or lust for verbose kudos.

然而这些人的动机，特别是曼德尔森勋爵，绝非单纯为了个人利益或是渴望听到滔滔不绝的赞美之词。

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The exception to this rule is, of course, if you have information that would be relevant to the calculation of any penalties and interest.

FORBES: A Beginner's Guide To Taxes: Fixing Your Mistakes

With the calculation of the impact of rising interest rates on debt repayments we have assumed that only the mortgage element rises.

BBC: NEWS