Question: During April 2025, did the daily changes (compared to the previous day) in the central parity rates of EUR/RMB, HKD/RMB, and USD/RMB always occur in the same direction (i.e., all rates increasing together or all rates decreasing together)?
Among the days when these rates did not move in unison, find the date when the USD/RMB central parity rate experienced its greatest increase. List the three central parity rates (EUR/RMB, HKD/RMB, USD/RMB) for that specific day, rounded to four decimal places.
Answer: No, the daily changes did not always occur in the same direction. 
The USD/RMB central parity rate experienced its greatest increase on April 8th. 
On that day, the EUR/RMB, HKD/RMB, and USD/RMB central parity rates were 7.9155, 0.9270, and 7.2038, respectively.
A marginal error of 0.01 is allowed.