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: - 85/68
- The prime factorizations of the numerator and denominator:
- 85 = 5 × 17
- 68 = 22 × 17
- 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 (85; 68) = 17
- 85/68 = - (85 ÷ 17)/(68 ÷ 17) = - 5/4
The fraction can also be reduced without calculating GCF; factor the numerator and denominator and cross out all the common prime factors:
- 85/68 = - (5 × 17)/(22 × 17) = - ((5 × 17) ÷ 17)/((22 × 17) ÷ 17) = - 5/4
The fraction: - 90/72
- 90 = 2 × 32 × 5
- 72 = 23 × 32
- GCF (90; 72) = 2 × 32 = 18
- 90/72 = - (90 ÷ 18)/(72 ÷ 18) = - 5/4
The fraction can also be reduced without calculating GCF; factor the numerator and denominator and cross out all the common prime factors:
- 90/72 = - (2 × 32 × 5)/(23 × 32) = - ((2 × 32 × 5) ÷ (2 × 32))/((23 × 32) ÷ (2 × 32)) = - 5/4
The fractions are equal.
This is one of the simplest cases when comparing two fractions.
Not only are the numerators of the fractions equal but their denominators are also equal.
::: The operation of comparing fractions :::
The final answer: