Lets first understand Riba....

Riba is a fixed profit, which absolves the lender from any risk factor and the risk factor is only borne by receiver....For example even if receiver's money is lost ,he is entitled to pay the profit to lender ,whether he earned 100 or lost 100....

I think in case of prize bonds,the interest is calculated and added in a single pool against each investment and then this interest is alloted to a single investor instead of distributing the share equally,according to the profit...

I am not quite sure about how they ascertain the profit here...Do the government decides profit according to the profit gained?


And gambling (occurance by chance/luck) is also prohibited in Islam....Because of lucky draw it is somewhat close to gambling..

And you remember the Hadith which asks to avoid doubtful things about which you are not sure that if they are halal or haram

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