This online calculator solves the four basic types of percent problems and percentage increase/decrease problem. The calculator will generate a step-by-step explanation for each type of percentage problem.
This calculator solves four types of percentage problems.
Type 1: What is 15% of 20?
This can be solved in two steps:
Step 1: Write 15% as a decimal number: 15% = 0.15
Step 2: Multiply 0.15 and 20 to get the answer: 0.15 * 20 = 3
Type 2: The number 25 is what percentage of 80?
This can be solved in two steps:
Step 1: Solve the equation: 80 * x = 25. The solution is x = 0.3125
Step 2: Multiply 0.3125 by 100% to get the answer: 0.3125 * 100% = 31.25 %
Type 3: The number 32 is 8% of what number?
As usual, this problem requires to steps:
Step 1: Write 8% as a decimal number: 8% = 0.08
Step 2: Divide 32 and 0.08: 32 ÷ 0.08 = 400
Type 4: percentage increase: What is the percentage increase from 20 to 90?
In this type of problem we use formula
$$ \text{Percentage increase} = \frac{\text{new amount} - \text{original amount}}{\text{original amount}} \cdot 100 \% $$Using our numbers we have:
$$ \text{Percentage increase} = \frac{90 - 20}{20} \cdot 100 \% = \frac{70}{20} \cdot 100 \% = 350 \% $$Type 4: percentage decrease: What is the percentage decrease from 160 to 40?
Now we will use formula
$$ \text{Percentage decrease} = \frac{\text{original amount} - \text{new amount}}{\text{original amount}} \cdot 100 \% $$Using our numbers we have:
$$ \text{Percentage decrease} = \frac{160 - 40}{160} \cdot 100 \% = \frac{120}{160} \cdot 100 \% = 75 \% $$Please tell me how can I make this better.