How to work with fractions (add, subtract, multiply, divide, and simplify)
A fraction has a numerator (top) and a denominator (bottom). The calculator handles addition, subtraction, multiplication, division, simplification, mixed numbers, and decimal ↔ fraction conversion.
Core rules
- Add/Subtract: Use a common denominator. If denominators differ, use the LCM (least common multiple).
- Multiply: Multiply numerators together and denominators together, then reduce.
- Divide: Multiply by the reciprocal of the second fraction.
- Simplify: Divide top and bottom by their GCD (greatest common divisor).
- Mixed ↔ Improper:
a b/c = (a×c+b)/c
; reverse by dividing and taking remainder.
LCM, GCD, and reducing steps
To add a/b + c/d
, use LCM(b,d)
as the common denominator. Scale each numerator:a×(LCM/b)
and c×(LCM/d)
, then combine and simplify by GCD(numerator, denominator)
.
To reduce n/d
, compute g = GCD(n,d)
and write (n/g)/(d/g)
. Mixed number: divide n ÷ d = q
remainder r
; result q r/d
.