You can just divide by a hundred and multiply by 3. Edit: You'd be surprised how good at calculating percentages you can be if you do them a lot. It just beco

You can just divide by a hundred and multiply by 3. Edit: You'd be surprised how good at calculating percentages you can be if you do them a lot. It just becomes automatic. Source: binged-watched Shark Tank, got real good at multiplying by percentages and their reciprocals in the process.