Question

Значение выражения $frac{5}{12} lk +(-frac{1}{6} lk)+lk+(4lk-14lk)$ равно...
1) 4lk
2) 5lk
3) $3frac{1}{4}$lk
4) $4frac{6}{12}$lk

Answer 1

$frac{5}{12} lk +(-frac{1}{6} lk)+lk+(4lk-14lk) =frac{5}{12} lk -frac{2}{12} lk+lk-10lk=\\1frac{3}{12} lk-10lk=1frac{3}{12} lk-9frac{12}{12}lk=-8frac{9}{12}lk=-8frac{3}{4}lk$