Normalize the denominator
The lab rewrites a negative denominator as a positive denominator with the sign moved to the numerator. This changes the notation while preserving the fraction's value.
Keep the sign with the value
Negative fractions follow the same equality and operation rules as positive fractions. Write the sign clearly, then inspect the exact arithmetic before interpreting the diagram.
Put it into practice
Distinguish the operation from the sign
Subtracting a negative value is different from subtracting a positive one. Read the complete operation before simplifying so a minus sign in an operand does not disappear into an unexplained shortcut.
Use graphics as a supplement
The relative-magnitude bars show absolute lengths with a sign label and a different color for negative values. They are not a full signed number line. The exact fraction result and written intermediate arithmetic remain the reference for your explanation.
A worked example
One half minus negative one third becomes three sixths minus negative two sixths, giving five sixths. The shared unit is unchanged; the sign determines how the quantities combine.
Exact fraction arithmetic and relative-magnitude visualizer
Fractions keep their meaning when the numerator and denominator are handled together. Enter two fractions to add, subtract or multiply, inspect the unreduced result and its simplification, and compare their relative magnitudes. Arithmetic uses exact integers rather than floating-point guesses.
The diagram shows relative magnitudes, not exact partitions of a whole. Signed fractions are supported, and denominators cannot be zero. Very large values can remain exact in the calculation while being too large for a useful browser graphic.
Inputs are processed in this page. Nothing is submitted to the app or a business. Download a result to keep it; this page does not automatically save your work.
What to keep in mind
This browser lab is an independent educational companion, not the app's protected student workflow. It deliberately offers an optional explanation and does not authenticate a parent or enforce the app's solution restrictions.
Continue exploring
Exact fraction arithmetic and relative-magnitude visualizer
Why adding fractions needs a common denominator
Understand fraction reduction without changing the value
Explore signs when adding, subtracting and multiplying fractions
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