arc ACD = 310
minor arc AD = 360 - (arc ACD)
minor arc AD = 360 - 310
minor arc AD = 50 degrees
Use the inscribed angle theorem to find that
angle ABD = (1/2)*(minor arc AD)
angle ABD = (1/2)*50
angle ABD = 25 degrees
Focus only on triangle ABD. We have a right angle at point A. So A = 90 degrees. B = 25 was found earlier (when we computed angle ABD). We just need angle D
A+B+D = 180
D = 180-A-B
D = 180-90-25
D = 65
Or as a shortcut,
D = 90-B
D = 90-25
D = 65
This shortcut works only because triangle ABD is a right triangle (angle B and angle D are complementary angles)
Answer: Angle ADB is 65 degrees