Question

1+{2-[3+(x-4):5]:6}•7=8

Answer 1

$1+(2-(3+\frac{x-4}{5} ):6)*7=8\\1+(2-\frac{3+\frac{x-4}{5} }{6} )*7=8\\1+(2-\frac{\frac{15+x-4}{5} }{6} )*7=8\\1+(2-\frac{\frac{11+x}{5} }{6} )*7=8\\1+(2-\frac{11+x}{30} )*7=8\\1+14-\frac{77+7x}{30} =8\\450-77-7x=240\\373-7x=240\\-7x=240-373\\-7x=-133\\x=19$