Here is a brainteaser from Michael Isichenko`s "Quantitative Portfolio Management: The Art and Science of Statistical Arbitrage".
Alice's model predicts the USD to EUR exchange rate to increase $10\%$ in one year. Bob's forecast indicates the same increase for EUR to USD rate over the same period. Can Alice and Bob both be right?
Can anybody help with the solution? I guess the answer should be "yes", but I do not really understand why.