2/7-5/9

Let's calculate: $\frac{2}{7}-\frac{5}{9}$

ⓘ Add fractions by using a common denominator and then adding their numerators. We choose $63$, the least common multiple of $7$ and $9$. Multiplying the numerator and the denominator by the same number does not change the fraction: $\frac{2}{7}-\frac{5}{9}$ = $\frac{2\times 9}{7\times 9}-\frac{5\times 7}{9\times 7}$ = $\frac{2\times 9-5\times 7}{7\times 9}$

$\frac{2\times 9-5\times 7}{7\times 9}$

ⓘ Perform multiplications before additions and subtractions: $2\times 9$ = $18$, $5\times 7$ = $35$

ⅰ $7\times 9$ = $63$

$\frac{18-35}{63}$

ⓘ The numerator and the denominator are computed before the division: $18-35$ = $-17$

▶Result:   $-\frac{17}{63}$

The numeric value of: $-\frac{17}{63}$ equals:

▷ $\approx -0.2698$