speed

On a recent flight from Phoenix to Kansas
City, a distance of 919 nautical miles, the plane arrived
20 minutes early.On leaving the aircraft, I asked the captain,
“What was our tail wind?”He replied, “I don’t know, but our
ground speed was 550 knots.” How can you determine if
enough information is provided to find the tail wind? If possible,
find the tail wind. (1 knot = 1 nautical mile per hour)