7/12-16/17

Let's calculate: $\frac{7}{12}-\frac{16}{17}$

ⓘ To add fractions, put them over the same denominator, then add the numerators. We choose $204$, the least common multiple of $12$ and $17$. Multiplying the numerator and the denominator by the same number does not change the fraction: $\frac{7}{12}-\frac{16}{17}$ = $\frac{7\times 17}{12\times 17}-\frac{16\times 12}{17\times 12}$ = $\frac{7\times 17-16\times 12}{12\times 17}$

$\frac{7\times 17-16\times 12}{12\times 17}$

ⓘ Multiplications are done before additions and subtractions: $7\times 17$ = $7\times (10+7)$ = $7\times 10+7\times 7$ = $70+49$ = $119$, $16\times 12$ = $16\times (10+2)$ = $16\times 10+16\times 2$ = $160+32$ = $192$

ⅰ $12\times 17$ = $(10+2)\times 17$ = $10\times 17+2\times 17$ = $170+34$ = $204$

$\frac{119-192}{204}$

ⓘ The numerator and the denominator are computed before the division: $119-192$ = $-73$

▶Result:   $-\frac{73}{204}$

The numeric value of: $-\frac{73}{204}$ equals:

▷ $\approx -0.3578$