1. Turn the percentage to a decimal. Since a percentage is in the tenth place, example: 10% = 0.10. So 25% will be turned to 0.25
2. Multiply 48 by 0.25
3. When you get the results, use the results you have just multiplied and subtract it to 48(example: 48x0.25=[result]. 48-[result])
4. Done!