Calculate percentages: find percent of a number, increase, decrease, and percentage difference.
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To find X% of Y, convert X to a decimal (divide by 100) and multiply by Y. Example: 25% of 200 = 0.25 × 200 = 50.
To increase Y by X%, calculate Y + (Y × X/100). This is the same as multiplying Y by (1 + X/100). Used for tips, markups, tax.
To decrease Y by X%, calculate Y - (Y × X/100). This is the same as multiplying Y by (1 - X/100). Used for discounts, depreciation.
The percentage difference between two values is |A - B| / ((A + B) / 2) × 100. It measures how different two values are relative to their average.
A calculator gives you an answer. It doesn't tell you which line of your working went wrong. Photograph your own steps — handwritten notebook, whiteboard, or a screenshot of an online assignment — and Math.Photos checks them line by line, then points at the exact step where the sign flipped.
Photo of your notebook, not a retyped expression.
"Line 3 dropped a negative", not just "wrong".
Questions that lead you to the fix, not the answer.
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Math.Photos solves any math problem from a screenshot — algebra, calculus, geometry, statistics, and more. With step-by-step explanations.
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