13/18-14/15

Let's evaluate: $\frac{13}{18}-\frac{14}{15}$

ⓘ To add fractions, put them over the same denominator, then add the numerators. We choose $90$, the least common multiple of $18$ and $15$. Multiplying the numerator and the denominator by the same number does not change the fraction: $\frac{13}{18}-\frac{14}{15}$ = $\frac{13\times 5}{18\times 5}-\frac{14\times 6}{15\times 6}$ = $\frac{13\times 5-14\times 6}{18\times 5}$

$\frac{13\times 5-14\times 6}{18\times 5}$

ⓘ Multiplications are done before additions and subtractions: $13\times 5$ = $(10+3)\times 5$ = $10\times 5+3\times 5$ = $50+15$ = $65$, $14\times 6$ = $(10+4)\times 6$ = $10\times 6+4\times 6$ = $60+24$ = $84$

ⅰ $18\times 5$ = $(10+8)\times 5$ = $10\times 5+8\times 5$ = $50+40$ = $90$

$\frac{65-84}{90}$

ⓘ Calculate the numerator and denominator before dividing: $65-84$ = $-19$

▶Result:   $-\frac{19}{90}$

The numeric value of: $-\frac{19}{90}$ equals:

▷ $\approx -0.2111$