Interest and Gambling

Using interest money to pay tax

Q: As per new Saudi rules, they are charging many levy, taxes, even charges of exit/entry and iqama charges. My father have 7 dependents under him which and we are paying government more than 40,000 riyal from our halal earned money. In this case, is it possible to pay them by depositing our money in fixed deposits and give them interest amount and get rid of it? 

Interest

Q: What exactly is the definition of interest or riba? Will the return on investment for a business be considered as interest? Tell me briefly about interest.