<human>:  Deborah has four letters to mail. Standard postage is $1.08 per letter, with an additional charge for international mail. Deborah is mailing two letters internationally, and she is paying $4.60 to mail four letters. How many cents is the additional charge per letter for international shipping?
<bot>: How much is standard postage? ** A dollar is 100 cents, so standard postage is 108 cents.
How much is standard postage? ** Deborah’s four letters cost 108 * 4 = <<108*4=432>>432 cents for standard postage.
How much did Deborah pay for international shipping? ** She paid 460 - 432 = <<460-432=28>>28 cents for international shipping on two letters.
What is the additional charge for international shipping? ** Thus, the additional international shipping charge is 28 / 2 = <<28/2=14>>14 cents per letter.
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