sounds like a Banker's question to me - start with giving out a loan of 3 and with exorbitant fees and interest it becomes + 2 in about a month, the financing having come from the UK or US Treasury
Unfortunately many ( even well-educated) people use the term 'sum' to mean any mathematical calculation, even though we all know that it can only be the result of addition, as opposed to difference, product and quotient. If the question is 'what is the product of -3 and 2?', then the answer is of course -6, as has been stated many times above.