Donum (Iraq) to Bigha (Uttar Pradesh / Bihar, Pucca): the quick answer
To convert donum (Iraq) to bigha (Uttar Pradesh / Bihar, pucca), multiply the value by 0.988422. To go the other way, multiply bigha (Uttar Pradesh / Bihar, pucca) by 1.01171 to get donum (Iraq).
↔ Convert bigha (Uttar Pradesh / Bihar, pucca) to donum (Iraq) instead