(7 3/16-5 1/4x)+3 3/4=9 1/16помогите ПОЖАЛУЙСТА!!! даю все баллы

Решите задачу:

$(7 \frac{3}{16} - 5 \frac{1}{4} x) + 3 \frac{3}{4} = 9 \frac{1}{16}$
$( \frac{115}{16} - \frac{21}{4}x ) + \frac{15}{4} = \frac{147}{16}$

$( \frac{115}{16} - \frac{21}{4}x )= \frac{147}{16} - \frac{15}{4}$
$- \frac{21}{4}x = \frac{147}{16} - \frac{15}{4} - \frac{115}{16}$
$- \frac{21}{4}x = \frac{147}{16} - \frac{100}{16} - \frac{115}{16}$
$- \frac{21}{4}x = \frac{132}{16}$
$x = \frac{132}{16} \times ( - \frac{4}{21} )$
$x = \frac{44}{28} = \frac{22}{14} = \frac{11}{7}$