B737 Next Generation Undifferentiated
Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Less Severe; Deviation - Speed All Types; Deviation / Discrepancy - Procedural Clearance
Flight Crew Became Reoriented; Flight Crew Returned To Clearance
Aircraft
Descending through 35;000 feet we had an airspeed disagree flag. During the arrival we had altitude disagree and EEC ALT both occur. We determined the Captain (CA) side was giving erroneous information. His airspeed was displaying 10-35 knots different from the standby and First Officer (FO) side. [Center] asked us to slow to 210. A few minutes later ATC asked our speed. We told him 240 and [were] trying to get it down to 210 since we had an unreliable airspeed problem. He said to slow to 190 and that he would pass that info along to the next controller.
B737NG First Officer reported a speed deviation occurred while they were dealing with an unreliable airspeed indicator.