100:(18+(82-10x):6)=5 .
18+(82 - 10х) : 6 = 100 : 5 .
18+(82 - 10х) : 6 = 20.
(82 - 10х) : 6 = 20 - 18 .
(82 - 10х) : 6 = 2 .
82 - 10х = 2 * 6 .
82 - 10х = 12 .
82 - 12 = 10х .
10х = 70.
х = 70:10 .
х = 7.
проверка: 100:(18+(82-10*7):6)= 100:(18+(82-70):6) = 100:(18+12:6) =
= 100:(18+2) = 100 : 20 = 5