1/2-1/19

Let's evaluate: $\frac{1}{2}-\frac{1}{19}$

ⓘ Add fractions by using a common denominator and then adding their numerators. We choose $38$, the least common multiple of $2$ and $19$. Multiplying the numerator and the denominator by the same number does not change the fraction: $\frac{1}{2}-\frac{1}{19}$ = $\frac{1\times 19}{2\times 19}-\frac{1\times 2}{19\times 2}$ = $\frac{1\times 19-1\times 2}{2\times 19}$ = $\frac{19-1\times 2}{2\times 19}$

$\frac{19-1\times 2}{2\times 19}$

ⓘ Multiplications are done before additions and subtractions: $1\times 2$ = $2$

ⅰ $2\times 19$ = $2\times (10+9)$ = $2\times 10+2\times 9$ = $20+18$ = $38$

$\frac{19-2}{38}$

ⓘ The numerator and the denominator are computed before the division: $19-2$ = $17$

▶Result:   $\frac{17}{38}$

The numeric value of: $\frac{17}{38}$ is:

▷ $\approx 0.4474$