Percentage Calculator
Five common percentage problems, solved as you type.
Five common percentage problems, solved as you type.
Percentages describe a part out of 100. To find X percent of Y, multiply Y by X and divide by 100. To find what percent X is of Y, divide X by Y and multiply by 100. Percentage change is the new value minus the old value, divided by the absolute old value, times 100. Use the increase and decrease card for discounts, price rises and tips, and the last card to work backwards to the original number.
To find a discount, use the first card: 25% of 80 is 20, so the sale price is 60. To check a mark, use the second card: 42 out of 60 is 70%. For price changes, use the third card, and remember that percentage change always depends on which value you treat as the starting point.
Moving from 10% to 12% is a rise of 2 percentage points, but a 20% increase relative to the starting value.
The second change applies to a larger number, so you end up 4% lower.