question: Stephen borrowed $300 from his sister and promised to return it with an additional 2% of the money he owed. For 11 months Stephen will give his sister $25 per month and the remaining amount, including the interest, will be paid on the twelfth month. How much will Stephen pay in the twelfth month?
answer: Stephen will pay an additional $300 x 2/100 = $<<300*2/100=6>>6.
  He should return a total of $300 + $6 = $<<300+6=306>>306.
  For eleven months Stephen will pay a total of $25 x 11 = $<<25*11=275>>275.
  Therefore, Stephen will pay 306 - 275 = $<<306-275=31>>31 on the twelfth month.
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