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: 20/40
- The prime factorizations of the numerator and denominator:
- 20 = 22 × 5
- 40 = 23 × 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 (20; 40) = 22 × 5 = 20
20/40 = (20 ÷ 20)/(40 ÷ 20) = 1/2
The fraction can also be reduced without calculating GCF; factor the numerator and denominator and cross out all the common prime factors:
20/40 = (22 × 5)/(23 × 5) = ((22 × 5) ÷ (22 × 5))/((23 × 5) ÷ (22 × 5)) = 1/2
The fraction: 28/42
- 28 = 22 × 7
- 42 = 2 × 3 × 7
- GCF (28; 42) = 2 × 7 = 14
28/42 = (28 ÷ 14)/(42 ÷ 14) = 2/3
The fraction can also be reduced without calculating GCF; factor the numerator and denominator and cross out all the common prime factors:
28/42 = (22 × 7)/(2 × 3 × 7) = ((22 × 7) ÷ (2 × 7))/((2 × 3 × 7) ÷ (2 × 7)) = 2/3