Simplify the operation
Reduce (simplify) the fractions to their lowest terms equivalents:
- To reduce a fraction to the lowest terms equivalent: divide both the numerator and denominator by their greatest common factor, GCF.
The fraction: - 21/45
- The prime factorizations of the numerator and denominator:
- 21 = 3 × 7
- 45 = 32 × 5
- Multiply all the common prime factors: if there are repeating prime factors we only take them once, and only the ones having the lowest exponent (the lowest powers).
- GCF (21; 45) = 3
- 21/45 = - (21 ÷ 3)/(45 ÷ 3) = - 7/15
The fraction can also be reduced without calculating GCF; factor the numerator and denominator and cross out all the common prime factors:
- 21/45 = - (3 × 7)/(32 × 5) = - ((3 × 7) ÷ 3)/((32 × 5) ÷ 3) = - 7/15
The fraction: - 25/50
- 25 = 52
- 50 = 2 × 52
- GCF (25; 50) = 52 = 25
- 25/50 = - (25 ÷ 25)/(50 ÷ 25) = - 1/2
The fraction can also be reduced without calculating GCF; factor the numerator and denominator and cross out all the common prime factors:
- 25/50 = - 52/(2 × 52) = - (52 ÷ 52)/((2 × 52) ÷ 52) = - 1/2